FRANKLIN  INSTITUTE  LIBRARY 

PHILADELPHIA,  PA. 


THE  CHEMISTRY  AND  PRACTICE 
OF  SIZING. 


Ninth  Edition  (American). 


Digitized  by  the  Internet  Archive 
in  2015 


https://archive.org/details/chemistrypracticOObean 


THE 


CHEMISTRY  AND  PRACTICE 
OF  SIZING. 

A  Practical  Treatise  on 

THE  SIZING  OF  COTTON  YARNS, 

PRACTICAL  SIZE  MIXING, 
TAPE  SIZING,  BALL  or  WARP  SIZING,  and  HANK  SIZING. 


WARP  BLEACHING  AND  TINTING.       HANK  BLEACHING. 
MILDEW  AND  IRON-STAINS. 
CLOTH  BLEACHING. 
THE  VENTILATING  AND  HUMIDIFYING  OF  WEAVING  SHEDS. 

P,Y 

PERCY  BEAN,  F.C.S.,  M.Ph.S. 

Author  of  "THE  CHEMISTRY  AND  PRACTICE   OF  FINISHING," 

AND 

F.  SCARISfc.tfiCK, r 

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SILVER   MEDALLIST,   ( Tl'Y  \A  N])'  G I UL  f>  S.  !  ]* 

NINTH  EDITION  (AMERICAN). 

Boston,  Mass.,  U.S.A.  : 
Lord  &  Nagle  Company,  144,  Congress  Street, 
Textile  Publishers. 
191 1 


c  c 


5  3 


PREFACE  TO  THE  NINTH  EDITION. 


HE  First  Edition  of  this  book  was  published 


JL  in  January,  1903,  and  it  was  immediately 
followed  by  an  edition  specially  printed  for  India. 
These  two  editions  were  sold  out  within  twelve 
months  of  publication,  and,  although  the  demand 
for  the  book  was  sufficient  to  warrant  a  third  edition, 
the  writer  was  unable  to  meet  the  requirements 
because  he  was  engaged  at  the  time  in  publishing 
"The  Chemistry  and  Practice  of  Finishing." 

The  third  edition  of  the  book  was  published  on 
October  1st,  1906,  followed  by  editions  for  the 
United  States  of  America  and  for  the  Continent. 

The  present  (ninth)  edition  has  been  completely 
re-written  and  much  new  matter  incorporated.  The 
practical  portion  on  Size  Mixing,  Tape  Sizing,  Warp 
Sizing-  and  Hank  Sizing  has  been  dealt  with  much 
more  fully  than  previously,  and  a  new  portion 
dealing  with  Warp  Bleaching  and  Tinting,  and 
Hank  Bleaching  has  been  added. 

Mr.  Fred  Scarisbrick  of  Darwen  has  again 
collaborated  with  me  in  the  chapter  on  Tape  Sizing. 
He   has  also   supplied   certain   special   matter  in 


vi.        The  Chemistry  and  Practice  of  Sizing. 


connection  with  a  series  of  personal  experiments 
conducted  with  the  aid  of  Dr.  Howarth,  Medical 
Officer  of  Health  for  Darwen,  for  the  purpose  of 
showing  the  effects  of  working  in  an  atmosphere 
having  a  high  "wet  bulb"  temperature. 

I  have  to  acknowledge  the  services  of  Mr.  Dan 
Scholefield  for  much  valuable  assistance  in  regard 
to  the  practical  side  of  Ball  and  Hank  Sizing  and 
Bleaching. 

I  beg  to  record  my  thanks  to  the  firms  who 
have  so  kindly  assisted  me  in  the  production  of 
the  book  by  supplying  the  blocks  for  the  Machinery 
illustrations,  etc. 

PERCY  BEAN. 

Textile  Laboratory, 

Marsden  Chambers, 

10,  Marsden  Street, 

Manchester. 

January  2nd,  igi I. 


CONTENTS. 


Introduction. 

PAGES. 

Classification  of  sizing  ingredients. 

Chemicals  and  the  chemical  apparatus  for  making  the 

various  tests  described  in  the  text      -  i  to  34 


Chapter  I. 

Substances  for  giving  Adhesive  Properties  to  the  Size. 

Starch. — tests  for— structure  of  granules  of — chem- 
ical composition  of— physical  properties  of — 
action  of  heat,  hot  water,  caustic  alkalies,  acids, 
various  chlorides,  borax,  diastase,  and  bacteria, 
on — identification  of  the  various  starches. 

Wheaten  Flour. — use  and  treatment  of  in  sizing — 
tests  for  quality  and  purity  of. 

Farina. — use  and  treatment  of  in  sizing — loss  in 
strength  of — varying  qualities  of. 

Maize  or  Corn-flour  and  Maize  Starch. — use 
and  treatment  of  in  sizing. 

Sago. — use  and  treatment  of  in  sizing. 

Tapioca. — use  and  treatment  of  in  sizing. 

Rice  Flour  and  Rice  Starch. — use  and  treatment 
of  in  sizing. 

Soluble  Starch. — preparation  of — use  and  treat- 
ment of  in  sizing. 

Dextrin. — use  and  treatment  of  in  sizing. 

Apparatine.  — manufacture  and  use  of  in  sizing. 

Gum  Tragacanth,  Gum  Tragasol,  Irish  and 

Iceland  Moss,  Glue  and  Bone  Size,  Glucose    35  to  133 


viii.      The  Chemistry  and  Practice  of  Sizing. 
Chapter  II, 

Materials  used  for  giving  Weight  and  Body  to 
the  Size  and  Yarn. 

China  Clay. — extraction  of — use  and  treatment  of  in 
sizing.  Advantages  of  using  powdered  China  clay. 

Sulphate  of  Barium. — use  of  in  sizing. 

Sulphate  of  Calcium  (sulphate  of  lime — gypsum) — 
use  of  in  sizing. 

Sulphate  of  Magnesium  (Epsom  salts). — use  of  in 
sizing. 

French  Chalk. 

Sulphate  of  Soda  (Glauber's  salts). — use  of  in  sizing. 

Silicate  of  Soda — Chloride  of  Barium     -       -  134  to  164 


Chapter  III. 

Ingredients  used  to  soften  the  Size  and  Yarn, 
Oily  and  Greasy  Substances. 

Tallow. — beef  and  mutton — tests  for  presence  of 
fatty  acids,  bone  fat  and  marrow  fat,  mineral 
oil  and  paraffin  wax,  cotton  seed  oil,  water, 
Yorkshire  grease,  stearic  acid  and  other  adulter- 
ants. 

Tallow. — melting  point,  vaporising  point,  flash  point 
specific  gravity  of — saponification  of — use  and 
value  of  in  sizing. 

Tallow  Substitutes. — analysis  of — composition  of 
— value  of. 

Bone  and  Marrow  Fats — Cocoa-Nut  Oil — Olive 
Oil — Palm  Oil — Castor  Oil — Oleine  Oil — 
Soluble  Oil — Stearine— Spermaceti 

Paraffin  Wax.  —  use  of  in  sizing — objection  to,  for 
goods  to  be  bleached — melting  point  of. 

Japan  Wax. — melting  point  of — use  of  in  sizing       -  165  to  205 


Contents, 


IX. 


Chapter  IV. 
Soap* 

Manufacture  of  soft  and  hard  soaps — composition 
and  quality  of — analysis  of — action  of  chloride 
of  magnesium,  chloride  of  zinc,  chloride  of  cal- 
cium, and  sulphate  of  magnesium  on — use  of  in 
sizing       --------  206  to  216 

Chapter  V. 

Deliquescent  substances  used  for  softening  and  for 
giving  Weight  and  Strength  to  the  Yarn. 

Chloride  of  Magnesium. — (so  called  antiseptic) — 
manufacture  of — analysis  of— tests  for  presence 
of  impurities  in — action  of  heat  on,  and  damage 
produced  in  cloth  by — use  and  abuse  of  in  sizing 
— iron  stains  caused  by — action  of  soap  on, 

Chloride  of  Calcium. — manufacture  of — impurities 
in — use  of  in  sizing. 

Glycerine. — manufacture  of — properties  of — adult- 
eration of — tests  for  presence  of  mineral  salts  in 
— glucose  as  an  adulterant  of. 

Glycerine  Substitutes. — composition  of — value  of 
— use  of  in  sizing. 

Glucose. — manufacture  of — properties  of — use  of  in 

sizing       -       -       -       -       -       -       -       -217  to  234 

Chapter  VI. 

Ingredients  used  for  preserving  Size  from  Mildew. 

Chloride  of  Zinc. — composition  of — manufacture 
of — iron  salts  in — physical  character  and  chem- 
ical properties  of — effect  of  adulerated  chloride 
of  zinc  on  cloth — impurities  and  adulterants 
found  in,  tests  for — specific  gravity  and  Twaddell 
of — use  of  in  sizing — quantity  necessary  to  pre- 
serve cloth  from  mildew. 


x.        The  Chemistry  and  Practice  of  Sizing. 


Salicylic  Acid. — uses  of — advantages  of  as  an 
antiseptic  in  pure  sizing,  and  for  coloured  borders. 

Carbolic  Acid  and  Cresylic  Acid. — uses  of  in 
light  sizing. 

Thymol. — Preparation  and  properties  of — antiseptic 

value  of  -------       -  235  to  261 

Chapter  VII. 
Size  Mixings,  and  the  Methods  and  Plant  employed 
in  Mixing  Size. 

Classification  of  Sizing. — pure  sizing — light  sizing 
— medium  sizing — heavy  sizing. 

Arrangement  of  Plant  in  Size  Mixing  Rooms  - 
mixing  becks — flour  becks — clay  pan — chloride 
of  magnesium  beck. 

Preparation  of  the  Ingredients  previous  to 
Mixing. — treatment  of  flour,  steeping  and  fer- 
menting—  method  of  mixing  the  flour — treatment 
of  starches,  China  clay,  chloride  of  magnesium. 

Method  of  Mixing  the  Sizing  Ingredients  for 
the  various  classes  of  size. 

Size  Mixings  for  various  weights,  from  pure  size  to 
160  per  cent. 

Sizing  for  Native  Dyeing. 

Size  Mixings  which  cause  tendering  when  the  cloth 
is  singed — effects  of  sizing  on  bleaching  and 
"finishing." 

Colours  used  for  Tinting  the  Size. — coal  tar 
colours,  basic  and  substantive — ultramarine  blue 
— indigo  blue — the  tinting  of  Egyptian  shades — 
damage  caused  by  improper  use  of  dyes.   -       -  262  to  314 

Chapter  VIII. 
Tape-Sizing. 

The  Tape  Frame  or  Slasher.— description  of — 
the  Creel — the  Sow  Box— the  Cylinders — the 
Headstock. 


Contents, 


XI. 


The  Creel — and  its  fittings. 

The  Sow  Box. -Feed  Pipe — Boiling  Pipes — Float 
Roller — Immersion  Rollers — Copper  Roller, 
Expansion  Joints  in  —  Finishing  Roller — Mid- 
feathers — Falling  Roller. 

The  Cylinders,  widths  of— double  acting  buckets — 
friction  bowls — ball  bearings — tension  of  the  yarn 
on. 

The  Headstock: 

The  Driving  Motion. — gearing — cone  drums 
and  how  to  remedy  their  defects — slow  motion. 
Friction  Motion — use  and  abuse  of. 
The  Draw  Roller  and  its  object — abuse  of 
the  draw  roller. 

The  Marking  or  Measuring  Motion. — single 
markers — dhootie  markers — three  mark  motions. 
The  Pressing  Motion. — variety  of — single  and 
double  roller  presses — friction  motion  on  pressing 
motion — press  rollers  and  rusty  flanges — amount 
of  press  for  various  sorts. 

Fans. — and  their  use. 

The  Wraith. — its  construction  and  use. 

The  Sheeting  Rollers  and  Crooked  Beams. 

The  Lease  Rods. 

The  Reducing  or  Equilibrium  Valve. — motion 
for  cutting  off  steam  to  the  cylinders  when  the 
machine  stops. 

Method  of  Weighting  the  Backbeams. 

The  Taper  or  Slasher.  — his  varied  responsibilities 
—  duties  of  a  taper — gaiting  a  "set" — "striking" 
— "laying  in" — good  beam  bottoms — 4  broken 
bottoms,"  and  how  to  avoid  them — over-dried 
yarn — how  to  prevent  yarn  being  unsized. 


xii.        The  Chemistry  and  Practice  of  Sizing. 


The  Practice  of  Tape  Sizing. 

Medium  and  Heavy  Sizing. — how  to  obtain  uniform 
weights  and  "feels" — uniform  feed  of  size — 
force  pump  and  its  construction — the  sieve  tap 

—  the  overflow  valve — the  self-feed  valve  — 
uniform  boiling  of  size,  and  how  to  obtain  it  — 
effect  of  partially  boiled  size  — size  boiling  pans 
— uniform  drying,  and  what  it  means — percent- 
age of  moisture  in  yarn — important  qualifications 
of  a  good  taper. 

Light  Weights  on  ''First  Beams." — their  cause, 
and  how  to  avoid  them. 

Soft  Beams. — and  how  to  avoid  them. 

How  to  obtain  a  good  "Finish"  on  the  Yarn. — 
the  finishing  roller  and  its  weight. 

Coloured  Tapeing. — the  coloured  box  and  its 
position — method  of  driving  and  suggested  alter- 
ations— slack  sides  and  their  prevention — 
advisability  of  running  the  grey  yarn  damper 
than  the  coloured,  and  methods  for  doing  same, 
reversing  the  direction  of  motion  of  the  big 
cylinder— cylinder  for  the  coloured  yarn — the 
coloured  back  beam  and  its  position  in  the  creel 

—  twirling  of  the  coloured  yarn,  and  how  to  avoid 

it — stripes  and  how  they  are  separated  -   315  to  390 


Chapter  IX. 

Ball  or  Warp  Sizing. 

The  Tinting  of  Yarns  in  the  Process  of  Sizing. 

Warp  Bleaching. 

BALL  or  WARP  SIZING.— processes  involved  in 
— object  of — effect  of  as  compared  with  tape 
sizing. 

Ball  Sizing  Plant. — mixing  becks — boiling  pan  — 
— sizing  machine — drying  machine. 


Contents. 


xiii. 


Sizing  Machine. — size  box — squeezing  apparatus — 
Method  of  applying  the  size  to  the  yarn — 
Mixings  for  coloured  and  white  yarns. 

Drying  Machine,  and  method  of  using. 

Balling  Machine,  and  its  use. 

Tinting  Ball  Sized  Warps. — blueing  bleached 
warps— imitation  bleached  warps — tinting  creams, 
pinks,  heliotropes,  greens. 

Topping  Indigo  Dyed  Yarns. 

Tinting  Imitation  Linen  Shades  on  Cotton. 

Warp  Bleaching. — method  of. 

Kier  Boiling  Process. 

Machine  Boiling  and  Bleaching. 

Boiling  and  Washing  xMachines. — squeezing  rollers 
— immersion  rollers — throw-out  gear — boil  pipes 
—  "overflow  "and  "let-off"  pipes — delivery  winch.  391  to  435 

Chapter  X. 
Hank  Sizing  and  Bleaching. 

HANK  SIZING. — advantages  of  in  special  cases- 
method  of  applying  the  size  to  the  yarn. 

Hank  Sizing  Plant. — single  hank  sizing  and  wring- 
ing machine — double  machine — brushing  machine 
— drying  stoves. 

Hank  Bleaching. — boiling,  washing,  chemicking, 
washing,  souring,  washing,  soaping  and  blueing, 
"stocking,"  washing,  hydro-extracting.       -       -  436  to  454 

Chapter  XI. 
The  Preparation  of  the   Yam  for  the  process 
of  weaving 
and  the  Testing  of  Sized  Yarn. 
The  Preparation  of  the  Yarn  for  the  Process 
of  Weaving. — faults  which  increase  the  weavers' 
work — importance  of  retaining  the  "elasticity"  of 
the  yarn — importance   of  good   warping  and 
tapeing. 


xiv. 


The  Chemistry  and  Practice  of  Sizing. 


The  Automatic  Loom. — speed  of  machinery  for 
producing  the  most  work — importance  of  strong 
yarn — waste  of  energy  by  use  of  poor  yarn — 
appearance  of  the  cloth — ring  yarn,  its  merits 
and  defects. 

The  Testing  of  Sized  Yarns. — unreliability  of 
testing  machines  for  this  purpose — "elasticity," 
misuse  of  the  term  as  applied  to  yarn — why  the 
testing  machines  are  useless  for  determining  the 
weaving  qualities  of  a  sized  yarn.  -  436  to  462 


Chapter  XII. 
The  Physical  and  Chemical  Properties  of  Cotton, 

and  the 

Chemical  and  Microscopical  Examination 
of  Textile  Fibres. 

Cotton. — composition  of — length  and  diameter  of 
fibres  of — cellulose  in  —  action  of  lime  in  bleaching 
on — mineral  matter,  oil  and  wax,  and  moisture  in. 

Over-damping  of  Cotton  Yarn. — mildew  produced 
by. 

Microscopical  examination  of  cotton,  linen,  hemp, 
wool,  and  silk  fibre. 

Chemical  examination  of  different  fibres — estimation 
of  wool  and  cotton  in  a  mixed  fabric — estimation 
of  cotton  and  linen  in  a  mixed  fabric — separation 
of  silk  and  cotton — separation  of  wool  and  cotton  463  to  480 


Chapter  XIII. 

The  Analysis  of  Sized  Grey  Cloth. 

Qualitative  Analysis — Quantitative  Analysis. — 
Determination  of  counts  of  yarn  from  small 
sample  of  cloth        -  481  to  511 


Contents, 


xv. 


Chapter  XIV, 
Damage  to  zuhich  Sized  Cloth  is  Liable. 
Mildeiv  and  Iron-stains, 

Mildew. — Black  and  green,  how  produced — yellow, 
purple,  pink,  brown,  and  brick-red  mildew — liability 
of  manufacturer  and  shipper — amount  of  chloride 
of  zinc  necessary  to  preserve  cloth  from  mildew 
— mildew  caused  by  excess  moisture  in  cloth — 
mildew  in  the  weaving  shed — development  of 
mildew  after  shipment  abroad — analyses  of 
mildewed  cloth  showing  cause  of  damage. 

Iron-Stains. — classification  of — cause  of — prevention 

of — "black  oil"  stains — removal  of   -  -  512  to  544 


Chapter  XV. 
Bleaching, — Faults  in  Sized  Cloth  which  cause 
Damage  when  Bleached  and  Finished. 

Bleaching  Cotton  Cloth. — Stamping  and  Stitch- 
ing, Washing  and  Steeping,  Washing  and  Lime- 
ing,  Bowking  and  Boiling  with  Lime,  Souring, 
Washing,  Souring,  Washing,  Soda  Ash  Boil, 
Washing,  Chemicking,  Souring,  Washing. 

Caustic  Process  of  Bleaching,  and  the  operations 
involved  therein. 

Scouring  or  Half  Bleaching  Process. 

Open  Bleaching. 

Bleaching  of  Cotton  Goods  Woven  with  Coloured 
Borders  and  Headings — list  of  dyes  suitable  for 
yarns  in  coloured  borders  and  headings — damage 
caused  by  use  of  unsuitable  dyed  yarns. 

Stains  and  Faults  due  to  Improper  Sizing,  and 
to  Imperfect  Bleaching. — Mineral  oil  stains — 
paraffin  wax  stains  —damage  from  use  of  chloride 
of  magnesium  in  the  size  -  -  545  to  583 


xvi.       The  Chemistry  and  Practice  of  Sizing. 


Chapter  XVI. 

The  Ventilation  of  Humidified  Weaving  Sheds. 

Weaving. — necessity  of  moist  atmosphere  for — effect 
of  east  winds  on — mean  temperature  of  outside 
air — effect  of  heating  atmosphere — relative 
humidity  of  outside  air. 

Effect  of  high   "wet   bulb"  temperatures  on 
operatives,  Mr.  Scarisbrick's  experiments. 

Table  of  Maximum  Limits  of  Humidity  allowed 
in  Weaving  Sheds. 

Science  of  Ventilating — 

Extraction  or  natural  principle — value  of  in 
weaving  sheds — method  of  placing  fans,  Union 
Engineering  Co.,  Darwen. 

Plenum  or  pressure  principle. — trunk  system,  centri- 
fugal fans  or  pressure  blowers,  Matthews  & 
Yates  Ltd  ,  James  Ho  worth  &  Co.  Ltd.,  Gregson, 
Great  Harwood. 


Humidifying  and  Cooling  Arrangements  -       -  584  to  6u 


Appendix  A — 

Flour  Milling      -  -  612  to  624 

Farina  and  Dextrin  commercially  considered  625  to  636 

Appendix  B — 

New  Process  of  Dyeing  -  637  to  639 

Appendix  C — 

Table  Comparing  Beaume  and  Tw7addell 
with  Specific  Gravity  together  with  Per- 
centage Table  of  Common  Chemicals        -  640  &  641 

Index     -------  i.  to  xii. 

Advertisements. 


LIST  OF  ILLUSTRATIONS. 


Page. 


Chemical  Apparatus         -       -       -              -            13  to  34 

Apparatus  for  the  Estimation  of  Starch  69 
Ball-bearing  Arrangement  for  Reducing  the  Friction  of  the 

Cylinder  Trunnions  (Tape  Frame)                        -  328 

Change  Wheel  Driving  Arrangement  (Tape  Frame)  -  -  333 
The  Driving  Motion,  with  Slow  Motion  arranged  to  Gear 

with  Driven  Cone  Drum  (Tape  Frame)  -  334 

The  Friction  Motion  (Tape  Frame)  -       -                      -  338 

Dhootie  Marking  Motion  (Tape  Frame)    -                      -  343 

Headstock,  showing  Two-Roller  Press  (Tape  Frame)         -  346 

One-Roller  Press,  with  Friction  Motion  (1  ape  Frame)       -  348 

Right  and  Wrong  Way  of  Weighting  the  Eackbeams  -       -  357 

Sieve  Tap        ---------  369 

Size  Pump  and  Over-flow  Valve  attached  to  Size  Beck       -  370 

Self-feed  Valve         -                                                  -  371 

Size  Boiling  Pan,  showing  Self-feed  Valve  -  376 

Size  Boiling  Apparatus     -       -                                    -  37  7 

Arrangement  of  Coloured  Sow  Box  -  -  383 
Arrangement  for  Running  the  Coloured  Yarn  next  to  the 

Surface  of  the  Drying  Cylinders      -                      -  387 

Warp  Sizing  Machine       -                                            -  399 

Vertical  Drying  Machine                                               -  409 

Balling  Machine  (Ball  Sizing)    -                                    -  410 

Walsh  Type  of  High  Pressure  Kier   -                             -  428 

Single  Hank  Sizing  and  Wringing  Machine                      -  439 

Double  Hank  Sizing  and  Wringing  Machine      -              -  441 

Brushing  and  Stretching  Machine  (Hank  Sizing)               -  445 

Hydro-Extractor       -       -              -                             -  452 

Cotton  Pod  and  Flower  of  gossypium  Herbaceum              -  464. 

Cloth  and  Yarn  Quadrant         -  485 

Soxhlet's  Fat  Extraction  Apparatus   494 

Howorth  &  Co.  Ltd.  Humidifying  and  Ventilating  Apparatus  611 


LIST  OF 


PLATES. 


Facing 
Page. 


Plate 

I. 

Microscopical  Appearance  of  Starch  Granules 

Ju 

Plate 

II. 

Rptnovinp'   thp  "  OvprhniThpn "    or  .Snrfarp 
Earth 

134 

Plate 

III. 

General  View  of  China  Clay  Mine. 

Plate 

IV. 

Great  Beam  Clay  Mine 

I40 

Plate 

V. 

Dorothy  Clay  Mine  - 

141 

Plate 

VI. 

Trethosa  Clay  Mine  (Refining  Floors) 

142 

Plate 

VII. 

Refining  Floors  (clearing  the  sand) 

143 

Plate 

Vila. 

Clay  Stream  entering  Refining  Floors 

I46 

Plate 

VIII. 

Final  Settling  Tanks 

147 

Plate 

IX. 

Interior  of  Clay  Kiln  or  "Dry" 

148 

Plate 

X. 

"Linhay"  (loading  China  Clay) 

J        \                    O                                  J  / 

I4Q 

Plate 

XL 

Arrangement  of  Size  Mixing  Machinery 

26q 

Plate 

XII. 

The  Tape  Frame  (Wm.  Dickinson  &  Sons) 

314 

Plate 

XIII. 

Size  Boiling  Apparatus 

Plate 

XIV. 

Ball  Sizing  Plant  - 

^Q7 

Plate 

XV. 

Magnified  Cotton  Fibres  - 

464 

Plate 

XVa. 

Mercerised  Cotton  Fibres. 

Plate 

XVb. 

Dead  Cotton  Fibres. 

Plate 

XVI. 

Flax  Fibres. 

Plate 

XVIa. 

,,       Hemp  Fibres. 

Plate 

XVII. 

Jute  Fibres. 

Plate 

XVIIa. 

, j               V>  lJUl  1  lUICo. 

Plate 

XVIIb. 

China  Grass  (Ramie)  Fibres. 

Plate  XVIII. 

,,        Raw  Silk  ribres. 

Plate  XVIIIa. 

„       Viscose  Fibres. 

Plate 

XIX. 

Union  Engineering  Co. 

Extraction  Fan,  vertically  driven  - 

605 

Plate 

XX. 

Matthews  &  Yates  Ltd. 

Ventilating  and  Humidifying  Apparatus 

607 

Plate 

XXI. 

James  Howorth  &  Co.  Ltd. 

Ventilating  and  Humidifying  Apparatus 

6lO 

INTRODUCTION. 


SIZING  is  the  most  important  preparatory 
process  to  which  cotton  yarns  are  subjected 
previous  to  their  being  woven  into  cloth.  It  is  one 
of  the  operations  in  manufacturing  which  requires 
sound  judgment  as  well  as  manual  dexterity  on  the 
part  of  the  operative.  More  than  this,  it  is  necessary 
for  the  manufacturer,  or  his  manager  who  is  really 
responsible  for  the  sizing,  to  possess  sufficient 
chemical  knowledge  of  the  various  substances  used 
in  sizing  to  get  the  best  results  at  the  lowest  possible 
cost.  It  is  remarkable  that,  until  quite  recently, 
so  little  importance  has  been  attached  to  the 
necessity  of  acquiring  the  chemical  knowledge 
so  essential  to  the  successful  carrying  out  of  the 
operations  upon  which  so  much  of  the  success  of  the 
after  process  of  weaving  depends. 

If  cotton  manufacturers,  or  their  managers, 
possessed  as  much  knowledge  of  the  chemical 
properties  of  the  materials  used  in  sizing,  as  they  do 
of  the  other  details  of  their  business,  there  would  be 


2  The  Chemistry  and  Practice  of  Sizing. 


no  need  for  such  a  work  as  this.  But  so  long  as  the 
study  of  chemistry  is  not  considered  an  essential 
part  of  the  training  of  a  cotton  manufacturer,  so 
long  will  the  results  obtained  in  sizing  be  matters 
of  chance. 

There  is  no  doubt  that  the  losses  suffered  in  the 
past,  and  the  losses  still  being  suffered,  are  due  in 
many  cases  to  the  absence  of  expert  knowledge  of 
the  properties  of  the  various  substances  used  as  in- 
gredients of  size,  and  these  losses  might  have  been, 
and  may  be,  avoided  by  a  knowledge  of  chemistry. 
Not  only  should  the  manufacturer  possess  chemical 
knowledge  in  order  to  prevent  damage  to  his  cloth, 
but  he  should  be  able  to  apply  this  knowledge  in 
order  to  place  his  sizing  on  the  most  economical 
basis.  It  is  astonishing  to  find  men,  who  can  see 
at  once  the  advantage  of  being  up-to-date  with 
their  machinery,  adhering  to  old  and  wasteful 
methods  in  their  sizing.  This  conservatism  is  due 
almost  entirely  to  the  fact  that  they  do  not  possess 
sufficient  chemical  knowledge  to  make  alterations  in 
their  sizing  arrangements,  whereas  they  are  perfectly 
familiar  with  the  machinery  used  in  their  business. 
Consequently  they  are  in  a  position  to  appreciate 
anything  which  is  an  improvement  in  machinery, 
but  fear  to  make  alterations  in  their  sizing. 
Many  of  the  leading  manufacturers  would  be 
astonished  at  the  amount  of  saving  which  could 
be  effected  in  their  sizing,  if  they  could  only  be 


Introduction. 


3 


persuaded  that  the  results  they  get,  could  be 
obtained,  equally  well,  at  a  very  much  less  cost.  The 
excessive  cost  of  many  sizes  is  due,  in  the  first 
place,  to  the  fact  that  manufacturers  continue 
to  use  secret  preparations,  which  are  sold  to  them 
at  prices  much  above  the  actual  value  of  the  in- 
gredients used  in  their  preparation,  and  in  the  second 
place  because  they  continue  to  use  ingredients  which 
are  incompatible,  and  therefore  utterly  useless  when 
mixed  together.  In  fact  they  are  generally  worse 
than  useless  inasmuch  as  they  are  positively  wasteful. 
Many  of  the  mixings  which  some  manufacturers 
pride  themselves  upon  as  being  superior  to  anything 
possessed  by  anyone  else  have  been  built  up  in 
the  most  haphazzard  way.  Probably  in  the  first 
instance  the  mixing  consisted  of  the  ordinary  in- 
gredients, such  as  flour,  starch,  China  clay,  tallow, 
chloride  of  magnesium,  and  chloride  of  zinc.  Then 
someone,  with  special  abilities  as  salesman,  has 
persuaded  the  manufacturer  that  the  addition  of  some 
particular  article  would  bring  about  some  wonderful 
result.  This  particular  ingredient  has  been  then 
added  to  the  size,  and  later  someone  else  has  per- 
suaded him  that  a  special  preparation  of  his 
own  is  the  one  thing  required  to  make  the  mixing 
a  perfect  size,  and  this  also  has  been  added.  So 
it  has  gone  on,  until,  in  time  it  has  been  for- 
gotten how  it  came  to  pass  that  a  mixing  contains 
a  dozen  ingredients  instead  of  about   half  that 


The  Chemistry  and  Practice  of  Sizing. 


number.        The    curious    thing    is    that    if  the 
manufacturer  only  knew  the  composition  of  the 
various    mysterious  ingredients   he    is   using,  he 
would  find  that  they  were  similar  to  those  in  general 
use,  excepting  that  they  contain  large  quantities 
of  added  water.     It  is  when  the  origin  of  a  mixing 
has  been  forgotten  that  the  manufacturer  believes 
that  he  possesses  something  of  very  particular  value 
not  possessed  by  other  manufacturers,  whereas  any 
and  every  mixing  in  use  to-day  could  be  matched 
with  a  choice  of  materials  ranging  not  more  than 
about  half-a-dozen  in  number.    Manufacturers  rarely 
consider  to  what  an  extent  they  place  themselves  in 
the  power  of  individuals  when  they  persist  in  the 
use  of  secret  preparations.       There  is  also  the 
possibility  that  the  particular  ingredient  is  not  only 
absolutely  wasteful,  but  it   may    be   actually  an 
injurious  substance  to  use  wTith  other  ingredients. 
As  a  matter  of  fact  the  authors  know  of  many  cases 
of  damage  caused  by  the  use  of  certain  substances 
which  by  themselves  have  no  injurious  properties. 
A  manufacturer  is  therefore  well  advised  to  keep 
his  size  mixings  as  simple  as  possible,  and  use  only 
those  substances,  the  composition  of  which  is  known 
to  him. 

The  sizing  of  yarns  dates  back  as  far  as  we  have 
any  history  of  woven  cotton  goods.  As  first  prac- 
tised in  Lancashire,  sizing  consisted  in  passing  the 
threads  of  warp  through  some  adhesive  substance, 


Introduction, 


5 


such  as  flour  paste,  and  afterwards  drying  them.  This 
gave  the  threads  the  necessary  strength,  but  they 
were  too  harsh  for  successful  weaving.  To  reduce 
this  harshness,  and  at  the  same  time  make  the  yarn 
more  pliable,  tallow  or  oil  of  some  description  was 
added  to  the  mixing,  and  this  gave  all  that  was 
requisite  for  successful  weaving. 

Later,  sizing  was  carried  out  with  the  idea  of 
producing  goods  which  should  possess  a  certain  feel 
in  the  grey  state.  These  goods  were  not  intended  to 
be  bleached,  but  were  intended  to  be  sold  and  used  in 
the  grey  state  only.  About  this  time  heavy  sizing 
also  began  to  be  largely  practised,  and  many 
substances  came  into  use  wThich  had  not  been  in 
use  previously.  Amongst  these  was  chloride  of 
magnesium,  a  substance  which  was  added  to  the 
size  for  the  purpose  of  softening  the  yarns  and  also 
for  improving  the  weaving.  It  was  an  ideal  sub- 
stance for  the  purposes  mentioned,  but  it  possessed 
one  feature  which  produced  effects  which  were 
never  anticipated  at  the  time.  Chloride  of  mag- 
nesium has  the  power  of  absorbing  moisture,  hence 
its  effect  in  strengthening  and  softening  the  yarn. 
But  this  absorption  of  moisture  also  has  the  effect 
of  making  the  starch  in  the  size  a  suitable  medium 
for  the  development  of  mildew  growths.  The 
results  were  disastrous  when  the  goods  were  shipped 
abroad.  Mildew  was  developed  during  the  passage 
out,  and  many  thousands  of  pounds  were  lost  before 


6  The  Chemistry  and  Practice  of  Sizing. 


antiseptics,  such  as  chloride  of  zinc,  etc.,  came  into 
general  use.  This  is  a  typical  instance  of  the  evil 
results  which  may  accrue  through  using  a  sub- 
stance, the  nature  of  which  is  totally  unknown  to 
the  user. 

It  was  about  this  time  that  heavy  sizing  became 
very  greatly  abused.  The  sole  object  some  of 
the  manufacturers  seemed  to  have  in  view,  was  how 
to  make  cloth  with  as  little  cotton  and  as  much  size 
as  it  was  possible  to  incorporate  together.  This 
heavy  sizing  was  carried  on  without  sense  or  reason 
and  many  manufacturers  paid  very  dearly  for  the 
experience  they  got. 

For  the  last  twenty  or  thirty  years  heavy  sizing 
has  been  carried  on  in  a  perfectly  legitimate  manner. 
There  is  a  demand  for  cheap  cotton  cloth  for  certain 
purposes,  and  this  demand  can  be  met  only  by  sizing. 
Such  cloth  is  sold  in  the  grey  state.  It  is  never 
washed,  but  used  in  the  condition  in  which  it  is 
received.  It  is  still  customary,  however,  for  persons 
unacquainted  with  the  cotton  trade  to  condemn  the 
policy  of  Lancashire  cotton  manufacturers  in  making 
heavily  sized  goods  for  export.  These  people  still 
believe  that  the  sole  object  of  sizing  is  to  defraud 
the  natives  who  purchase  the  cloth,  whereas  the 
natives  know  perfectly  well  what  they  are  getting, 
and  there  is  no  question  of  their  being  imposed 
upon.  As  a  matter  of  fact  heavily  sized  goods  are 
more  suitable  than  pure  calico  for  many  purposes. 


Introduction. 


7 


It  would  be  a  very  unfortunate  thing  for  Lancashire 
if  the  demand  for  heavily  sized  goods  should  cease, 
unless  the  natives  of  India  and  China  were  able  to 
pay  the  additional  price  for  pure  cotton  cloth.  It  is 
a  matter  of  common  knowledge,  however,  that 
heavy  sizing  is  generally  on  the  decrease,  and  this 
is  due,  in  the  authors'  opinion,  to  the  fact  that  the 
world  is  becoming  richer,  and  people  are  now  able 
to  purchase  more  highly  priced  goods  than  they 
were  formerly  in  a  position  to  purchase. 

SUBSTANCES  USED  IN  SIZING, 

A  large  number  of  substances  have  been  intro- 
duced for  sizing  purposes  at  one  time  or  another. 
Some  of  them  have  stood  the  test  of  time,  whilst 
others  have  been  short  lived.  There  are  three 
important  points  to  consider  when  determining  the 
value  of  a  substance  to  be  used  for  sizing.  In  the 
first  place  it  must  be  low  in  price.  In  the  second 
place  it  must  have  no  detrimental  properties  as  re- 
gards its  action  on  the  weaving.  In  the  third  place 
it  must  be  free  from  injurious  impurities  or  latent 
defects  which  would  cause  damage  to  the  cloth  after 
it  is  woven.  The  following  list  of  ingredients  in- 
cludes practically  the  whole  of  those  in  regular  use 
at  the  present  time,  and  they  may  be  divided  into 
five  great  classes,  viz.  : — 


The  Chemistry  and  Practice  of  Sizing. 

For  giving  Adhesive  Properties  to  the  Size. 
Wheaten  Flour 
Farina  (Potatoe  Starch). 
Maize  or  Corn  Starch. 
Sago. 

Rice  Flour. 

Rice  Starch. 

Tapioca. 

Dextrin. 

Soluble  Starch. 

Iceland  and  Irish  Moss. 

Apparatine. 

Gum  Tragacanth. 

Gum  Tragasol. 

Materials  for  giving  Weight  and  Body  to  the 
Size  and  Yarn. 

China  Clay. 

Sulphate  of  Magnesium  (Epsom  Salts). 
Sulphate  of  Calcium  (Sulphate  of  Lime  or  Gypsum). 
Sulphate  of  Soda  (Glauber's  Salts). 
Sulphate  of  Barium  (Barytes). 

Materials  for  "Softening"  the  Size  and  Yarn. 
( Direct  Softeners ). 

Tallow  of  various  kinds. 
Palm  Oil. 
Castor  Oil. 
Cotton  Seed  Oil. 

Oleine  Oil  (Alizarine  Oil  or  Turkey  Red  Oil). 

Cocoanut  Oil. 

Soluble  Oil. 

Stearine. 

Paraffin  Wax. 

Japan  Wax. 

Spermaceti. 

Soap  of  various  kinds. 
Glucose. 


Introduction. 


9 


4.  Materials  for  Softening  and   giving   Weight  to 

the  Size  and  Yarn.  ( These  substances  act  as  softeners 
by  absorbing  moisture,  and  so  produce  good  weaving). 

Chloride  of  Magnesium. 
Chloride  of  Calcium. 
Glycerine. 

5.  For  Preserving  the  Size  from  Mildew   and  De- 

composition. 

Chloride  of  Zinc. 
Carbolic  Acid. 
Cresylic  Acid. 
Salicylic  Acid. 
Glycerine. 
Thymol,  &c,  &c. 

From  what  has  been  said  already  it  will  be 
seen  how  very  necessary  it  is  that  manufacturers 
should  arrange  to  have  their  sizing  ingredients 
tested  or  analysed.  This  should  be  done  for  three 
reasons  :  firstly,  to  ascertain  whether  they  are  free 
from  adulteration  or  injurious  impurity;  secondly, 
whether  they  are  equal  in  quality  and  strength  to 
the  samples  originally  submitted  by  the  dealer  ;  and 
thirdly,  whether  they  are  equal  to  those  previously 
in  use. 

With  this  object  in  view  it  has  been  considered 
advisable  to  give  details  of  the  various  tests  and 
methods  of  analyses  used  in  the  Laboratory,  many 
of  which  may  be  made  by  men  who  have  received 
no  chemical  training  whatever. 

In  a  work  of  this  description  the  authors  have  to 
face  two  difficulties.    In  the  first  place  it  is  necessary 


io        The  Chemistry  and  Practice  of  Sizing. 


to  cater  for  the  requirements  of  the  practical  man 
whose  knowledge  of  chemistry  may  be  nil.  In  the 
second  place,  the  book  is  written  for  the  use  of 
students  who  have  had  the  benefit  of  some  chemical 
training  at  one  or  other  of  the  Technical  Schools. 
To  neglect  the  description  of  the  chemical  apparatus 
used  in  making  the  various  tests  hereinafter  de- 
scribed, would  be  to  fail  in  a  matter  most  essential  to 
the  practical  man  who  desires  to  obtain  the  required 
knowledge,  whilst  the  risk  remains  of  wearying 
those  students  who  have  got  past  the  need  of  such 
details.  In  the  face  of  such  a  position  the  authors 
feel  justified,  in  spite  of  the /act  that  they  lay  them- 
selves open  to  adverse  criticism  on  the  grounds  that 
the  subject  is  one  for  an  elementary  text  book  on 
chemistry,  in  giving  full  details  of  many  simple  tests, 
and  also  a  full  description  of  the  chemical  apparatus 
necessary  to  carry  out  these  tests.  That  this  matter 
may  not  be  a  constant  scource  of  irritation  to 
advanced  chemical  students,  the  authors  propose  to 
discuss  this  portion  of  the  subject  in  the  introductory 
part  of  the  book,  by  this  means  keeping  the 
elementary  description  in  a  place  to  which  easy 
reference  may  be  made  at  a  later  stage.  This  will 
prevent  many  needless  repetitions  in  the  description 
of  the  tests,  and  whilst  avoiding  wearying  one  class 
of  students,  will  not  be  neglecting  the  interests  of 
the  other  class. 

The  following  is  a  list  of  some  of  the  most 


Introduction. 


important  pieces  of  apparatus  which  the  manu- 
facturer's laboratory  should  contain,  a  detailed 
description  of  which  is  given  later  : — 

Chemical  Balance. 

Set  of  Weights  (Metric). 

Microscope. 

Steam-bath  or  Drying  Oven. 

Water-bath. 

Bunsen's  Burners. 

Retort  Stand  with  rings. 

Mortar  and  Pestle. 

Platinum  Crucible. 

Porcelain  Crucibles. 

Iron  Wire  Triangles. 

Crucible  Tongs. 

Test  Tubes. 

Test  Tube  Stand. 

Funnels. 

Filter  Papers. 

Nest  of  Lipped  Beakers. 

Nest  of  Round  Beakers. 

Porcelain  Evaporating  Basins. 

Cylindrical  Test  Glasses. 

Watch  Glasses  and  Clip. 

Thermometer  Fah.  2120 

Thermometer  Fah.  6oo° 

Hydrometers. 

Blue  and  Red  Litmus  Paper. 

Other  apparatus  may  be  added  according  to  the 
requirements  and  advancement  of  the  reader,  but 
the  above  list  includes  all  that  is  necessary  to  make 
any  test  likely  to  be  undertaken  by  the  practical  man, 
and  indeed  many  valuable  tests  may  be  made  when 
the  operator  possesses  only  a  few  test  tubes,  beakers, 
and  evaporating  basins. 


1 2         The  Chemistry  and  Practice  of  Sizing. 


The  following  list  of  Chemicals  or  Reagents 

will  be  required,  and  should  be  stored  in  six  or 

eight  ounce  stoppered  bottles,  properly  labelled. 

SOLUTIONS. 

Dilute  Hydrochloric  Acid. 
Strong  Hydrochloric  Acid. 
Dilute  Sulphuric  Acid. 
Strong  Sulphuric  Acid. 
Strong  Nitric  Acid. 
Solution  of  Ammonia. 

„  Ammonium  Chloride. 

„       „  Ammonium  Oxalate. 

,,  Ammonium  Carbonate. 

„  Ammonium  Sulphide. 

„       „  Ammonium  Phosphate. 

„       „  Ammonium  Molybdate. 
„  Caustic  Soda. 

„  Barium  Chloride. 

„  Silver  Nitrate. 

„       „  Iodine. 

„  Ferrocyanide  of  Potassium. 

The  above  solutions  may  be  bought  ready  pre- 
pared and  of  the  right  strength,  or  the  solids  may 
be  obtained,  and  dissolved  in  distilled  water. 
Where  large  quantities  are  used  the  latter  method 
is  the  cheaper,  but  the  manufacturer  will  probably 
find  he  has  less  waste  by  getting  the  solutions. 
Other  chemicals  are  mentioned  under  certain  tests 
in  the  text,  and  where  these  tests  are  made  it  will 
be  necessary  to  obtain  them. 

THE  BALANCE.— The  balance  is  a  most 
essential  piece  of  apparatus  in  a  manufacturer's 
laboratory,  and  very  little   practice   is  necessary 


Introduction,  1 3 

to  enable  anyone  with  moderate  ability  to  use  it 
successfully. 

The  instrument  consists  of  a  rigid  metallic  lever 
or  beam,  suspended,  near  its  centre  of  gravity,  on  a 


fulcrum  or  pivot ;  the  masses  to  be  weighed  or  com- 
pared being  also  suspended  from  pivots  placed  at 
the  extremities  of  the  beam,  equidistant  from,  and  in 
the  same   perpendicular  plane    with    the  central 


14        The  Chemist7y  and  Practice  of  Sizing. 


fulcrum.  The  beam  has  the  shape  of  an  acute 
rhomboid  ;  this  particular  form  combines  lightness 
with  rigidity  and  strength.  On  the  possession  of 
these  qualities  depends  the  sensibility  of  the  balance. 
Through  the  centre  of  the  beam  passes  a  triangular 
piece  of  hardened  steel,  or  agate,  termed  a  knife  edge, 
the  lower  edge  of  which  turns  upon  a  horizontal 
plate  of  polished  agate  connected  with  the  pillar. 
At  the  end  of  each  arm  is  a  similar  knife  edge  fixed 
in  the  reverse  position,  and  bearing  an  agate  plate 
from  which  depend  brass  or  steel  hooks  to  hold  the 
pan  suspensions. 

The  terminal  knife  edges  are  fixed  in  brass 
settings  and  admit  of  being  adjusted  so  as  to  bring 
them  into  exactly  the  same  plane  with  the  middle 
edge.    Their  relations  to  the  middle  knife  edge 

o  o 

may  be  altered  by  means  of  the  little  adjusting 
screws  at  the  sides. 

The  efficiency  of  the  balance  depends  to  a  large  ex- 
tent on  the  preservation  of  the  sharpness  of  the  knife 
edges,  and  the  absolute  smoothness  of  the  agate 
planes  ;  it  is  therefore  desirable  to  prevent  their  con- 
tact wThen  the  balance  is  not  in  use.  This  is  effected 
by  means  of  a  frame  which  lifts  the  middle  knife  edge 
from  the  middle  plane.  At  the  extremities  of  the 
frame  are  steel  points  which  enter  into  little  hollows 
in  the  lower  surface  of  the  pan  suspensions  and  raise 
them  from  the  terminal  knife  edges.  The  frame 
is  attached  to  a  rod  descending  through  the  pillar 


Introduction. 


l5 


and  connected  with  an  eccentric,  worked  by  a  screw, 
with  a  milled-head,  situated  on  the  outside  of  the 
balance  case,  by  means  of  which,  the  rod,  and  with 
it  the  frame,  can  be  raised  or  lowered. 

The  movements  of  the  beam  are  indicated  by 
a.  vertical  pointer  which  swings  in  front  of  an 
ivory  scale  fixed  to  the  pillar.  This  ivory  scale  is 
graduated,  usually  into  20  parts,  the  middle  point, 
or  zero,  being  exactly  behind  the  needle  when  the 
beam  is  horizontal.  Any  inequality  in  the  weight 
of  the  arms  is  compensated  by  means  of  a  small 
vane  fixed  on  the  top  of  the  beam  above  the  middle 
knife  edge  which  may  be  turned  to  the  right  or  left 
as  required.  The  stability  of  the  beam  is  regulated 
by  the  aid  of  a  weight  termed  the  gravity \ bob,  which 
can  be  moved  along  the  rod  attached  to  the  upper 
edge  of  the  beam,  over  the  middle  knife  edge  on 
which  the  vane  works. 

In  order  to  protect  the  balance  from  acid  fumes, 
etc.,  and  to  prevent  air  currents  interfering  with  its 
action  during  the  operation  of  weighing,  it  is  enclosed 
in  a  glass  case,  the  back,  front,  and  sides  of  which 
can  be  opened  at  will.  The  case  is  supported  on 
levelling  screws,  by  which  it  can  be  adjusted  to  a 
horizontal  position  in  accordance  with  the  indica- 
tions of  the  spirit  level  attached  to  the  bottom 
of  the  case. 

The  balance  should  be  placed  in  a  room  where 
the  amount  of  vibration  is  as  little  as  possible,  and 


1 6        The  Chemistry  and  Practice  of  Sizing. 

should  not  be  moved  from  the  position  determined 
upon.  If,  on  commencing  to  weigh,  the  balance  be 
found  not  in  equilibrium,  the  beam  and  pans  should 
be  lightly  brushed  with  a  camels-hair  pencil,  and 
again  tested.  Care  should  always  be  taken  to  close 
the  door  of  the  balance  case  after  using. 


Set  of  Gramme  Weights. 


The  Weights.  —  In  all  the  operations  of  weigh- 
ing described  in  the  book,  the  authors  have  used  the 
metric  system,  not  only  because  it  is  the  usual  one 
in  analysis  but  because  it  is  the  simplest,  and  bears 
a  direct  relationship  to  the  standards  of  length  and 
capacity. 

A  set  of  weights  extending  from  50  grammes  to 
a  centigramme  (T^o  part  of  a  gramme)  will  be  found 


Introduction.  1 7 

most  generally  useful.  Such  a  set  should  contain 
the  following  : — 

Grammes.         Grammes.        Gramme.  Gramme. 

5°    5    °*5      =  0<05 

20    2    0*2    O  02 

IO    2    0*2    0*02 

IO    I    O'l       fc   O'OI 

The  fractions  of  a  gramme  below  the  second 
place  of  decimals  may  be  obtained  by  the  use  of  a 
rider,  wThich  is  sold  with  the  weights.  This  is  placed 
on  the  beam  of  the  balance.  The  beam  is  grad- 
uated into  10  divisions,  each  division  representing 
1  milligramme  (xoW  Part  °f  a  gramme) ;  these 
divisions  are  subdivided  into  '25,  -5,  and  75  of  a 
milligramme. 

In  using  the  weights,  they  should  be  taken  from 
the  box  by  means  of  the  forceps,  and  on  no  account 
touched  with  the  fingers.  The  weights  should  not  be 
used  haphazzard,  but  the  one  judged  to  be  required 
should  be  put  on  the  pan  first.  If  it  be  too  heavy, 
the  next  lighter  one  should  be  used,  first  replacing 
that  previously  tried  in  its  proper  position  in  the 
box.  If  this  be  too  light,  the  next  smaller  weight 
must  be  added,  and  so  working  down  to  the  smallest 
weight,  and  finally,  by  using  the  rider,  obtaining 
the  milligrammes  necessary. 

The  student  should  not  only  be  able  to  ascertain 
the  total  weights  used  by  counting  them  on  the  pan 
of  the  balance,  but  he  should  ascertain  this  total,  as 

B 


1 8         The  Chemistry  and  Practice  of  Sizing. 


a  check,  by  calculating  from  the  empty  holes  in 
the  box.  The  greatest  care  should  be  taken  to 
orotect  the  weights  from  the  action  of  acid  fumes 
and  dust. 

In  using  the  balance,  the  object  to  be  weighed  is 
placed  on  the  left  hand  pan  facing  the  operator,  and 
the  weight  on  the  right  hand  pan.  It  is  more  often 
necessary  to  find  the  weight  of  a  substance  than  to 
weigh  a  certain  quantity  of  it,  consequently  it  is 


Woolleys'  Balance. 


easier  to  place  weights  on  the  right  hand  pan  than 
on  the  left.  This  method  of  weighing  is  the  reverse 
of  that  which  is  usually  practised  with  ordinary 
scales  and  weights. 


Introduction. 


19 


It  must  be  carefully  borne  in  mind,  that,  when- 
ever a  weight  is  put  on  or  withdrawn  from  the  pan 
the  motion  of  the  beam  must  be  arrested.  Under 
no  circumstance  must  anything  be  placed  on  or  re- 
moved from  the  pans  when  the  beam  is  free  to 
oscillate. 

For  commercial  work  it  is  not  necessary  to  have  the 
most  delicate  balance.  Messrs.  James  Woolley,  Sons 
&  Co.  Ltd.,  Victoria  Bridge,  Manchester,  supply  a 
very  suitable  one  (page  18)  which  is  known  as 
Woolley's  balance.  It  is  contained  in  a  glass  case, 
having  a  counterpoised  front  sliding  frame.  This 
balance  has  agate  knives  working  on  agate  planes, 
beam  division,  rider  apparatus  and  tw7o  riders,  im- 
proved arrestment,  beam  support,  set-screws,  and 
pendulum  apparatus  for  levelling.  It  is  made  to 
carry  100  grammes  in  each  pan,  and  turns  with  one 
milligramme.    The  price  is  £/\.  4s. 

A  more  delicate  instrument,  working  on  a  new 
principle,  is  showm  on  page  20.  This  balance  carries 
200  grammes  in  each  pan  and  indicates  TV  milli- 
gramme. It  has  a  gilt  gun-metal  beam  and  column. 
The  beam  is  circular  instead  of  straight,  and  is  fitted 
with  adjustable  agate  knife  edges  and  agate  planes, 
pan  supports  and  arrestments  for  the  beam  and  pan 
suspenders,  rider  slides,  platinised  pans,  compensat- 
ing stirrup  suspenders,  levelling  screws  and  plummet. 
The  balance  is  contained  in  a  polished  mahogany 
and  glass  case,  having  sliding  windows  back  and 


20        The  Chemistry  and  Practice  of  Sizing. 


front,  doors  at  the  sides,  and  a  black  slate  base. 
The  price  is  £9  15s. 

THE  MICROSCOPE.— This  very  essential 
instrument,  an  illustration  of  which  is  shown  on  page 
21,  is  known  as  the  compound  microscope.  It  is  a 
combination  of  two  lenses,  one,  acting  as  the  object 
glass,  being  known  as  the  objective,  the  other  as  the 
eye  piece.  They  are  fitted  into  a  double  tube,  which 
admits  of  the  motion  of  the  eye  piece  so  as  to  suit  all 
sights.  The  tube  is  usually  set  nearly  vertical;  the 
object  to  be  viewed  being  placed  beneath  the  object 
glass  at  a  distance  a  little  beyond  its  focal  distance. 
The  rays  from  each  point  of  the  object  collect  after 


Introduction. 


refraction  at  a  focus  ;  the  result  being  an  inverted 
image  of  the  object  formed  in  the  tube.  This  image 
is  then  viewed  by  the  eye  piece  exactly  as  the 
original  object  is  viewed  by  the  simple  microscope. 
In  the  best  microscopes  the  eye  piece  is  not  a 
single  lens,  but  a  combination  of  two,  the  magnifying 


The  Microscope. 


The  above  microscope  is  one  introduced  by  Messrs.  James  Woolley,  Sons 
&  Co.  Ltd.,  and  is  suitable  for  any  work  required  by  the  manufacturer.  It  has  a 
very  firm  and  compact  horse-shoe  base,  and  is  provided  with  a  sliding  draw 
tube,  coarse  rack-work,  and  fine  adjustments.  It  is  inclinable,  and  has  plane 
and  concave  mirrors.  This  microscope  is  fitted  with  one  eye  piece  and  two 
high-class  achromatic  object  glasses,  viz.  :— a  \  in.,  magnifying  170  diameters 
which  can  be  increased  to  340  diameters  with  the  draw  tube,  and  a  I  in,, 
magnifying  from  40  to  85  diameters,  The  whole  is  packed  in  a  mahogany 
case,  price  £\  15s. 


22 


The  Chemistry  and  Practice  of  Sizing. 


power  of  which  is  greater  than  could  conveniently 
be  obtained,  on  account  of  spherical  aberration  and 
chromatic  effects,  by  a  single  lens.  Achromatic 
arrangements  are  now  indispensable  in  a  really 
efficient  microscope,  in  the  construction  of  which 
such  names  as  Ross,  Nachel,  Beck,  Tolles,  Spencer, 
Powell,  etc.,  are  world-famed. 

Reagent  Bottles. — The  most  useful 
size  has  a  capacity  of  8  or  10  ounces. 
They  may  be  obtained  either  with  paper 
or  white  enamelled  labels. 


Test  Tube  Stand. 

Weighing  Bottle. — This  bottle  is  used 
for  weighing  dried  cotton,  which  must  not  be 
weighed  exposed  to  the  air  on  account  of  its 
power  of  absorbing  moisture.    It  is  furnished 
with  a  well  fitting  glass  stopper. 
Watch  Glasses  and  Clip. — These  are  used 
when  determining  the  amount  of  moisture  in  sub- 
stances in  the  form  of  powder,  such  as  flour  and 

starch,  etc.  The  watch  glasses 
are  ground  to  fit,  so  as  to  keep 
the  substance  free  from  con- 
tact with  the  air  whilst  weigh- 
ing.   The  following  description  shows  the  method  of 


Introduction.  23 

using : — -A  pair  of  watch  glasses  and  a  clip  are 
carefully  weighed  on  the  balance  ;  two  or  three 
grammes  of  the  substance  to  be  weighed  are  placed 
on  the  lower  watch  glass,  the  upper  one  is  then 
replaced  and  fastened  with  the  clip,  and  again 
weighed  ;  the  increase  in  weight  gives  the  amount 
of  the  substance  taken. 

The  glasses  are  now  carefully  separated  and 
placed  in  the  drying  oven  for  two  or  three  hours,  the 
upper  glass  is  then  replaced,  fastened  with  the  clip, 
cooled,  and  weighed  again.  The  loss  in  weight  re- 
presents moisture.  It  is  necessary  after  the  first 
weighing  to  transfer  to  the  drying  oven  again  for 
one  hour  ;  after  cooling,  the  weight  is  again  taken, 
and  if  it  has  remained  constant  the  whole  of  the 
moisture  has  been  removed. 

The  following  is  an  example  of  the  determina- 
tion of  moisture  in  a  sample  of  starch  :  — 

Weight  of  watch  glasses,  clip  and  starch... 35*348  grammes, 
do.         watch  glasses  and  clip   32'4I7  » 


do.        starch  taken   2*931  ,, 

After  drying  : — 

Weight  of  watch  glasses,  clip  and  starch. ..34*967  grammes 
do.        watch  glasses  and  clip   32'4!7  » 

do.        dry  starch  2 '55°  >> 

Starch  taken  ,     ...    2*931  grammes. 

After  drying    2  550  „ 

Loss — moisture    ...    0*381  „ 

Thus  2*931  grammes  contained  0*381  gramme  of  moisture. 
This  calculated  to  a  percentage  gives  12*99%  of  moisture  in 
the  sample. 


24        The  Chemistry  and  Practice  of  Sizing. 


Steam  Bath. — This  bath  or  oven  is  a  double 
cased  box,  made  of  copper;  the  space  between  the 
two  cases  is  filled  with  water,  and  is  heated  by  means 

of  the  Bunsen  s  flame.  The 
steam  is  either  allowed  to 
escape  at  the  top,  or  con- 
ducted by  means  of  suit- 
able tubes  to  the  funnel, 
thus  preventing  too  rapid 
evaporation  taking  place. 
It  may  also  be  arranged 
that  a  constant  supply  of  water  is  dropped  into  the 
funnel,  and  the  excess  removed  by  attaching 
a  piece  of  rubber  tubing  to  the  copper  tube  at 
the  funnel  and  leading  to  the  sink.  This 
apparatus  keeps  a  fairly  constant  temperature  of 
about  2io°  Fah.,  and  may  be  used  for  drying 
cotton  cloth,  etc. 

Air  Oven. — This  is  simply  a  box  made  of 
copper.  It  is  heated  by  means  of  a  Bunsen's  flame, 
and  the  temperature  may  be  regulated  by  the  height 
of  the  flame  used  for  heating  it.  It  is  suitable  for 
drying  substances  where  a  higher  temperature  than 
the  boiling  point  of  water  is  desired.  If  used  for 
drying  substances  like  cotton  cloth  or  yarns,  care 
must  be  exercised,  as  these  substances  will  scorch 
when  the  thermometer  registers  little  more  than 
2  12°  Fah. 

Funnels. — These  are  of  various  capacities.  The 


Introduction. 


25 


sizes  suitable  for  filtering  ordinary  precipitates  are 
from  one  to  two  inches  in  diameter  at  the  top. 

Funnel  Stand. — 
This  stand  is  used  as  a 
support  for  the  funnels, 
and  may  hold  one  or 
two  as  desired. 

Filter  Paper. — The 
operation  of  filtering*  a 
mixture  is  a  very  neces- 
sary and  frequent  one. 
For  this  purpose  a  kind 
of  blotting  paper  is  used. 
Two  qualities  should 
be  obtained;  one  for  quantitative  analysis,  the  per- 
centage of  ash  of  which  is  known,  the  other  an 
ordinary  white  filter  paper  for  qualitative  work. 
They  may  be  bought  the  exact  size  required,  and 
should  be  folded  so  as  to  form  a  cone.  This  is  placed 
in  a  suitable  funnel  and  the  mixture  to  be  filtered 
poured  over  it.  In  quantitative  analysis  this  oper- 
ation requires  very  careful  performance;  the  mixture 
should  not  be  poured  directly  into  the  filter  paper, 
but  down  a  glass  rod  held  to  the  lip  of  the  vessel 
containing  the  mixture.  By  this  means  none  of 
the  mixture  is  lost  by  running  down  the  outside 
of  the  vessel. 

Wash  Bottle. — This  is  used  for  the  pur- 
pose of  washing  precipitates  with  either  hot  or 


26        The  Chemistry  and  Practice  of  Sizing. 


cold  water.  It  consists  of  a  glass  flask  fitted 
with  a  rubber  or  glass  stopper 
having  two  holes.  Two  pieces 
of  glass  tubing  are  bent  as 
shown  in  the  illustration,  and 
placed  in  position.  Water  is 
forced  from  the  lowrer  tube  by 
blowing  down  the  upper  one. 
Where  hot  or  boiling  water  is  re- 
quired the  flask  may  be  heated 
over  a  Bunsen's  flame. 
Specific  Gravity  Bottle. — This  bottle  is  made 
to  hold  a  certain  fixed  volume,  and  is  used  for  the 
purpose  of  accurately  determining  the  specific 
gravity  of  liquids  ;  it  is  used  as  follows  : — 
A  dry  specific  gravity  bottle,  having  a  counter- 
poise, is  rinsed  out  once  or  twice  with  the 
sample  of  the  liquid  to  be  tested,  and  allowed 
to  drain  for  a  few  minutes.  It  is  then  filled 
up  to  the  mouth  with  the  sample  to  be  weighed 
and  the  stopper  inserted.  The  excess  of  liquid  is 
forced  out  through  the  opening  in  the  stopper 
of  the  bottle.  The  outside  of  the  bottle  is  wiped 
perfectly  dry,  taking  care  not  to  hold  it  in  direct 
contact  with  the  hands,  otherwise  the  temperature 
of  the  body  will  cause  the  liquid  to  expand  and 
force  it  out  of  the  hole  in  the  stopper,  so  causing 
an  error  of  observation. 

The  bottle    and  contents   are  placed  on  the 


Introduction. 


27 


balance,  with  the  counterpoise  on  the  opposite  pan. 
Weights  are  added  until  the  balance  is  in  equilibrium. 
The  weight  found  is  divided  by  the  weight  of  water 
the  bottle  holds.  Specific  gravity  bottles  usually 
hold  25  grammes  of  water  at  6o°  Fah.,  and  are  sold 
with  a  counterpoise. 

The  following  calculation  will  show  the  student 
how  to  obtain  the  specific  gravity.  A  bottle  holding 
25  grammes  of  water  at  6o°  Fah.  held  37*575 
grammes  of  chloride  of  zinc  solution  at  the  same 
temperature.  37*575  25 ;  =  1*503  specific  gravity. 
From  these  figures,  the  degrees  Twaddell  may  be 
obtained  by  dividing  the  figures  after  the  decimal 
point  by  5.  Thus  503  -*-  5  =  ioo'6°T.  Con- 
versely, the  specific  gravity  may  be  found  by 
multiplying  the  degrees  Twaddell  by  5  and 
adding  1,000,  the  specific  gravity  of  water  being 
taken  as  1,000. 


Test  Glass — This  glass  is 
used  for  holding  liquids,  such  as 
caustic  soda,  acids,  etc.,  whilst 
ascertaining  their  specific  gravity 
by  means  of  the  hydrometer. 

Twaddell's  Hydrometers. — 
These  instruments  are  used  for 
showing  the  specific  gravity  of 
liquids  heavier  than  water.  In 


Twaddell's  scale  each  degree  is  equal  to  (5  +  1,000) 
the  specific  gravity  of  water  =  1,000.    The  hydro- 


28        The  Chemistry  and  Practice  of  Sizing. 

meters  are  numbered  from  i  to  6,  showing  sp.  g.,  as 
follows  : — 


No. 

i  . 

o°  to     24°  = 

sp.  g.  1000  to  1 1 20 

No. 

2  . 

..  24°  to    4S0  = 

„     1 1 20  to  1 240 

No. 

3  • 

..  48°  to    74°  = 

„     1240  to  1370 

No. 

4  • 

0  ,  0 
..  74  to  102  - 

„     1370  to  1510 

No. 

5  • 

..102°  tO    T380  = 

1510  to  1610 

No. 

6  . 

..138°  to  170°  — 

„     1690  to  1850 

These  may  be  obtained  either  singly  or  in  the 
set  of  six.  In  taking  the  Twaddell  of  a  liquid,  it 
should  always  be  at  a  temperature  of  6o°  Fah. 

Glass  Beakers — Two  kinds  are  required.  No. 
1  is  made  of  thin  Bohemian  glass   with  a  spout, 

No.  2  is  conical  in  shape ; 
this  latter  is  useful  for 
digesting  cloth  in  the 
quantitative  determin- 
ations described  under 
cloth  analysis.  These 
beakers  stand  hot 
No.  1.  No.  2.         liquids,    and    may  be 

heated  by  means  of  the  Bunsens  flame  if  it  be 
not  applied  direct.  A  piece  of  copper  gauze 
should  be  placed  on  the  tripod  stand,  or  ring  of 
the  retort  stand,  and  the  Bunsen's  burner  placed 
underneath. 

Separating  Funnel. — This  instrument  is  used 
for  separating  such  mixtures  as  the  ethereal  solution 
of  fatty  acids,  or  hydrocarbon  oils,  from  the  aqueous 


Introduction. 


29 


solution    of    soap,    as   described    in  the 
analysis  of  tallow.     The  most  convenient 
size    of   separating    funnel    for  general 
use  is  one  having  a  capacity  of  200  c.c. 
It  should  be  pear  shaped,  fitted  with  a 
well-ground  glass  stopper,   and    a  glass 
stop-cock  for  running  off  the  lower  layer 
from  a  mixture.     The  end  of  the  stem 
should  be  filed  off  in  an  oblique  manner 
to  prevent  any  liquid  remaining  in  it. 
Dessicator. — This  piece  of  apparatus 
is  used  for  placing  crucibles,  and  evaporating  basins 
etc.,  in,  whilst  cooling.     The  air  in  the 
dessicator  is  kept  free  from  moisture 
by  means  of  strong  sulphuric  acid,  or 
dried  chloride  of  calcium,  contained  in 
a  small  beaker,  placed  at  the  bottom. 
Evaporating  Basins. — It  is  necessary  to  have 
a  number  of  assorted  sizes  of  these  useful  articles. 

The  smaller  sizes  are  used  for 
evaporating  small  quantities  of 
liquids,  and  the  larger  ones  for 
many  other  purposes,  details 
of  which  are  given  in  the 
text.  The  evaporating  basin  recommended  by  the 
authors  is  that  known  as  Royal  Berlin  porcelain. 
They  are  rather  more  expensive  than  the  ordinary 
kind,  but  they  stand  heating  much  better.  Basins  of 
the  following  capacity  will  be  found  most  useful,  viz. : — 


30        The  Chemistry  and  Practice  of  Sizing. 


2  ounces,  4  ounces,  6  ounces,  8  ounces,  and  for  boil- 
ing cloth,  for  the  purpose  of  removing  the  size,  one 
should  be  obtained  having  a  capacity  of  40  ounces. 

Water  Bath. — This  is  used  for  evaporating 
liquids  where  the  naked  Bunsen's  flame  may  not 
be  used.  It  consists  of  a  copper  bowl  or  basin  with 
a  number  of  rings,  fitting  one  within  the  other, 
adapted  to  take  different  sizes  of  evaporating  basins. 
It  is  useful  for  evaporating  such  substances  as  ether, 

or  alcohol,  where  a  flame 
must  not  be  applied  directly 
to  the  basin.  The  method 
adopted,  in  these  cases,  is  to 
heat  the  water  in  the  bath  to 
boiling  point;  turn  out  the  gas  and  place  the 
evaporating  basin  containing  the  ether  on  the  bath. 
With  alcohol,  the  Bunsen's  flame  may  be  allowed  to 
continue  the  heating,  but  with  ether  this  should 
never  be  attempted,  as  this  substance  is  so  very 
inflammable,  and  is  certain  to  take  fire.  The  water 
bath  should  be  used  with  the  Soxhlet's  apparatus  to 
boil  the  ether  in  the  flask  when  extracting  fatty 
matter  from  cotton  cloth,  see  chapter  on  cloth  analysis. 

Thermometers. — There  are  two  Thermometers 
in  common  use,  the  one  by  Fahrenheit,  which  is 
generally  used  by  commercial  men,  and  in  everyday 
life  ;  the  other,  the  Centigrade,  which  is  in  almost 
general  use  amongst  scientific  men  and  in  labor- 
atories.   The  divisions  in  both  are  purely  arbitrary, 


Introduction. 


3i 


excepting  two  points  on  each,  viz.  :  those  which 
indicate  the  freezing  point  and  the  boiling  point  of 
water. 

In  the  Fahrenheit,  the  freezing  point  is  taken 
at  32°,  and  the  boiling  point  at  21  2°;  whilst  in  the 

Centigrade,  the  freez- 


1 00 


_  170 

- 

-  150 


too*  Boiling  Point. 

-  %o 

-  TO 


nig 


_  o*  Freezing  Point. 


point  is  at  o°, 
and  the  boiling  point, 
at  ioo°. 

It  is  easily  seen 
that  the  interval  be- 
tween the  freezing 
point  and  the  boiling 
point  in  the  Fahren- 
heit scale  is  divided 
into  180  equal  divis- 
ions or  degrees,  whilst 
in     the  Centigrade 

Fahrenheit.       Centigrade.  Scale  the  Same  interval 

is  divided  into  100  degrees. 

Conversion  of  Thermometry  Scales. 
It  is  frequently  necessary  to  convert  degrees 
Fah.  into  degrees  C.  and  conversely.    For  this  pur- 
pose the  following  formulae  will  be  found  useful : — 

1 .  To  convert  degrees  Fah.  into  degrees  C. 

(Fah— 32)  x  5_c 
9 

2.  To  convert  degrees  C.  into  degrees  Fah. 


C.  x  9 


+  32  =  Fah. 


2        The  Chemistry  and  Practice  of  Sizing, 


EXAMPLES. 

i.  What  temperature  on  the  Centigrade  scale  is  equal  to 
i2°  Fah.  ? 

212  -  32  =  180 


180  x  5  900 
 =  =  ioo° 


Ans.  =  ioo°C. 


9  9 

2.  What  temperature  on  the  Centigrade  scale  is  equal  to 
Fah.? 

9  -  32  =  ~  32 
-  32  x  5     -  160 
 =  =  -  i7°77C 


3.  Express  6o°  C.  on  Fahrenheit's  scale. 

60  x  9  540 
 108 

5  5 

Ans.  108  +  32  =  1400  F. 

4.  Express  —  150  C.  on  Fahrenheit's  scale. 

-  15  x  9     ~  J35 
 =  =  -  27 


5 


Ans.  -  27  +  32  =  50  F. 


Crucible  Tongs. 


Crucible. 


Triangle, 


Introduction. 


33 


Crucible. — For  most  ignitions  porcelain  cruci- 
bles may  be  used,  those  known  as  Royal  Berlin 
being  the  best.  In  certain  work  a  platinum  crucible 
is  necessary. 

Triangles. — These  are  used  for  supporting  the 
crucible,  and  are  made  from  iron  wire  and  pieces 
of  pipe  stem,  or  from  iron  wire,  as  shown  in  the 
illustration. 

Tripod  Stand. — This  stand 
is  usually  about  ten  inches  in 
height,  and  is  used  for  support- 
ing crucibles,  beakers,  etc.  In 
the  latter  case,  a  piece  of  iron  or 
copper  gauze  is  placed  on  the 
stand  so  as  to  prevent  the  contact 
^  of  the  naked  flame  with  the 
beaker. 

Retort  Stand. — This  stand 
with  rings  and  clamps,  etc.,  is 
used  for  holding  retorts  and  con- 
densers, or  for  supporting  wire 
gauze  or  triangles  on  which  beakers, 
evaporating  basins,  or  crucibles 
are  placed.  The  rings  may  be 
raised  or  lowered  on  the  upright 
to  the  required  height.  The 
clamps,  not  shown  in  the  illus- 
tration, are  used  to  hold  con- 
densers, etc. 


34        The  Chemistry  and  Practice  of  Sizing. 


Indicators. 

Litmus  Paper. — Litmus  paper  is  used  for  test- 
ing for  the  presence  of  free  acid  or  free  alkali.  Blue 
litmus  paper  is  turned  red  in  the  presence  of  all  acids, 
and  red  litmus  paper  is  turned  blue  in  the  presence 
of  alkalies. 

Litmus  is  useful  for  determining  the  presence  or 
absence  of  acids,  but  it  does  not  indicate  the  nature 
of  the  acid,  i.e.,  whether  mineral  or  organic. 

Methyl  Orange. — A  solution  of  methyl  orange 
dye  is  a  most  useful  indicator  because  it  distinguishes 
between  mineral  acids  and  organic  acids.  In  the 
presence  of  mineral  acids  and  also  oxalic  acid  it  be- 
comes pink,  but  it  is  not  affected  by  most  organic 
acids.    The  dye  must  be  used  in  a  very  dilute  form. 

Congo  Red. — This  dye  is  even  more  sensitive 
to  mineral  acids  and  oxalic  acid  than  methyl  orange. 
In  a  neutral  or  alkaline  solution  it  is  red,  but  in  the 
presence  of  theabove-mentioned  acids  itisturned  blue. 

The  advantages  of  a  reagent  which  can  be  used 
to  differentiate  between  mineral  acids,  which  are  most 
injurious  to  cotton  fibre,  and  organic  acids,  which 
are  harmless,  will  be  at  once  apparent,  especially 
when  it  is  necessary  to  determine  the  cause  of 
damage.  Litmus  would  be  useless  for  such  a  pur- 
pose because  it  is  acted  upon  by  weak  organic  acids, 
and  size  almost  invariably  contains  acids  of  this  kind, 
due  to  decomposition  of  starchy  matter,  or  to  the 
presence  of  free  fatty  acids  in  the  tallow. 


Starch. 


35 


Chapter  I. 

Substances  for  giving  Adhesive 
Properties  to  Size. 

WHEATEN  FLOUR,  FARINA,  MAIZE  OR 
CORN  STARCH,  SAGO,  RICE  FLOUR,  RICE  STARCH 
TAPIOCA,  SOLUBLE  STARCH,  DEXTRIN,  GUMS,  &c. 


STARCH,  in  one  form  or  another,  is  the  most 
important  substance  used  for  giving  adhesive 
properties  to  the  size,  and  strength  to  the  yarn.  It 
is  obtained  for  commercial  purposes  from  various 
sources,  but  principally  from  the  seeds  of  wheat,  rice, 
and  maize,  the  pith  of  plants  (sago),  and  roots  and 
tubers  (tapioca  and  farina).  Starch  is  found  in  cells  in 
almost  every  part  of  plants.  In  its  fully  developed 
state  it  is  most  abundant  in  the  matured  structures, 
such  as  seeds,  roots,  pith,  and  other  internal  structures. 
Starch  first  makes  its  appearance  as  minute  granules, 
in  the  interior  of  the  chlorophyl  grains,  when  exposed 
to  sunlight.  These  granules  are  chemically  acted 
upon,  and  dissolved,  and  the  solution  £orm^d,i& passed 


36 


The  Chemistry  and  Practice  of  Sizing. 


down  from  cell  to  cell  until  they  reach  certain  por- 
tions of  the  plant  structure,  where  they  are  reformed, 
and  stored  as  a  reservoir  of  food  for  future  use  in 
the  plant's  economy. 

Pure  starch  is  a  white  glistening  powder.  It  is 
an  amorphous  non-volatile  substance.  When  viewed 
under  the  microscope,  each  variety  may  be  recog- 
nised by  the  characteristic  size  and  shape  of  the 
granules  (see  plate  i.).  Starch  is  insoluble  in  cold 
water,  alcohol,  ether,  or  chloroform.  It  forms  a 
mucilage  with  glycerine  when  heated  with  this 
substance  and  water.  On  boiling  in  water  alone  the 
granules  swell  to  many  times  their  original  bulk 
apparently  going  into  solution,  but  that  this  is  not 
the  case  may  be  proved  by  passing  the  liquid  through 
very  fine  filter  paper.  The  filter  paper  retains  the 
starch,  allowing  only  the  water  to  pass  through. 
Intense  cold  will  also  precipitate  the  starch  from 
the  water. 

Test  for  Starch. —  Iodine  has  the  property  of 
colouring  starch  a  beautiful  indigo  blue.  This  colour 
is  destroyed  on  boiling.  In  testing  for  the  presence 
of  starch,  the  substance  under  examination  should 
first  be  boiled  with  water,  then  allowed  to  cool,  and 
a  solution  of  iodine  added.  The  colour  is  not  pro- 
duced in  the  presence  of  free  alkali,  and  if  this  be 
present  it  must  be  neutralised  with  acetic  acid.  In 
the  presence  of  free  mineral  acid,  and  oxalic  acid, 
the  boiling' must  not  be  too  prolonged,  otherwise  the 


The  Structure  of  Starch  Granules. 


37 


starch  will  be  converted  into  sugar  and  so  remain 
undetected. 

Chemical  Composition  of  Starch  (C6H10O5). — 
Starch  is  a  compound  consisting  of  carbon  combined 
with  the  elements  of  water,  hydrogen  and  oxygen. 
It  never  occurs  in  a  pure  state,  but  is  always 
associated  with  a  small  quantity  of  mineral  matter. 

Structure  of  Starch  Granules — Starch 
granules,  when  examined  under  the  microscope  with 
a  sufficiently  high  power,  are  found  to  consist  of  a 
series  of  distinctly  stratified  concentric  layers.  The 
outer  layers  are  denser  than  those  near  the  hilum. 
This  appearance  is  specially  marked  in  farina  starch. 

The  starch  granule  consists  of  the  true  starch 
compound  and  water  ;  the  compound  itself  being 
composed  of  two  substances,  viz.,  granulose  and 
cellulose.  Granulose  exists  in  the  starch  granule  to 
the  extent  of  about  95  per  cent,  and  the  cellulose, 
which  is  known  as  starch  cellulose  and  is  closely 
allied  in  its  chemical  properties  to  granulose,  occurs 
to  the  extent  of  about  5  per  cent. 

Starch  cellulose  exists  in  a  greater  proportion  in 
the  outer  layers  of  the  starch  granules.  This  portion 
is  the  oldest  part  of  the  granule,  and  in  all  probability 
cellulose  forms  the  entire  coating  of  the  granule. 

To  the  presence  of  this  protective  coating  is  to 
be  attributed  the  fact  that  starch  granules,  when 
intact,  are  absolutely  unacted  upon  by  cold  water. 
Although  water  is  absorbed  to  a  very  great  extent 


38        The  Chemistry  and  Practice  of  Sizing. 


by  the  granulose,  none  of  this  substance  is  able  to 
diffuse  into  the  surrounding  medium.  If,  however, 
the  outer  layer  of  the  granules  be  ruptured,  water  is 
rapidly  absorbed,  and  the  cell  contents  become 
swollen  to  a  very  great  extent,  and  a  small 
portion  of  the  granulose  is  rendered  soluble.  By 
repeatedly  treating  the  ruptured  granules  with  water, 
the  whole  of  the  granulose  may  be  removed,  and 
the  cellulose  left  behind  in  the  form  of  extremely 
thin  layers.  This  cellulose,  when  treated  with  iodine 
solution  is  coloured  a  dirty  yellow,  whilst  starch 
granulose  is  coloured  an  intense  indigo  violet  colour. 

Granulose  may  be  separated  from  starch  cellulose 
by  the  action  of  saliva,  diastase,  and  cold  dilute 
mineral  acids.  Dilute  sulphuric  acid,  two  per  cent 
strength,  removes  granulose  after  prolonged  contact, 
but  the  readiest  way  to  effect  the  separation  is 
to  treat  starch  paste  with  diastase  or  cold  extract 
of  malt.  This  reaction  takes  only  a  few  minutes, 
and  the  cellulose  may  be  separated  by  filtration. 
The  residue,  which  is  almost  pure  cellulose,  should 
then  be  well  washed  with  cold  water.  Starch 
cellulose  obtained  in  this  wray  is  absolutely  insoluble 
in  cold  water,  and  it  is  not  acted  upon  by  water  heated 
to  180  degrees  Fah.,  nor  by  a  cold  solution  of 
diastase.  Boiling  water  converts  a  portion  of  it  into 
soluble  starch,  but  even  prolonged  boiling  does  not 
render  it  entirely  soluble.  Starch  cellulose  is 
rendered  entirely  soluble  by  treating  it  with  dilute 


Starch  Cellulose. 


39 


caustic  soda  or  caustic  potash.  If  the  solution  formed 
be  treated  with  an  excess  of  acetic  acid,  the  cellulose 
may  be  precipitated.  But  if  this  solution  be 
previously  boiled,  acetic  acid  will  not  precipitate  it. 

The  question  of  starch  cellulose  is  an  important 
one  from  the  sizer's  point  of  view,  as,  in  the  authors' 
opinion,  much  of  the  difference  in  the  properties  of 
the  various  starches  is  due  to  the  character  and  state 
of  combination  in  which  cellulose  exists  in  the  starch 
granule.  There  is  a  marked  difference  in  the 
physical  properties  of  size  made  from  wheaten  starch, 
maize,  rice,  farina,  tapioca  and  sago.  Maize  and 
rice  give  a  harsh  stiff  feel  to  the  yarn,  which  no 
reasonable  amount  of  boiling  will  remove.  Wheaten 
starch,  farina,  and  tapioca,  on  the  other  hand,  give  a 
softer  and  more  mellow  feel.  The  difference  in  the 
characteristics  of  these  starches  is  generallyattributed 
to  the  shape  of  the  various  granules,  but,  after  boiling, 
the  granules  lose  their  shape  entirely,  and  this  cannot 
account  for  the  difference  in  physical  properties 
shown  by  the  different  starch  pastes. 

In  experiments  made  by  the  authors  it  has  been 
shown  that  when  maize  is  partially  converted  into 
soluble  starch  by  the  action  of  hydrochloric  acid  gas, 
it  resembles  wheaten  starch  in  its  properties,  and 
there  is  ample  scope  for  further  investigation  into 
this  matter. 

The  action  of  heat  on  the  various  starches  also 
goes  to  prove  the  authors'  contention  that  the  outer 


40        The  Chemistry  and  Practice  of  Sizing. 


layer  of  cellulose  of  the  starch  granule  is  the 
determining  factor  in  the  nature  of  the  paste  produced 
by  boiling  the  various  starches  in  water.  It  has  been 
found  by  experiment  that  these  layers  of  the  starch 
granule,  which  are  rich  in  granulose,  are  readily 
converted  into  soluble  starch  and  dextrin  on  heating, 
whilst  those  rich  in  cellulose  undergo  this  trans- 
formation only  after  prolonged  treatment.  1 1  has  also 
been  proved  by  experiment  that  rice  starch,  and  to 
a  less  degree  maize  starch,  shows  the  greatest 
resistance  to  heat,  whereas  such  starches  as  farina, 
tapioca,  wheat  and  sago,  are  much  more  readily 
transformed  into  soluble  starch  and  dextrin. 

Action  of  Hot  Water  on  Starch. — It  has  been 
previously  stated  that  starch  is  gelatinised  by  hot 
water.  The  temperture  at  which  this  is  brought 
about  differs  with  the  various  starches.  The  follow- 
ing table  shows  the  temperature  at  which  complete 
gelatinisation  occurs  : — 


Classes  of  Starch. 

Temperature  at 
which  complete 
gelatinisation 
takes  place. 

1 76°  Fah. 
1790  Fah 
1670  Fah. 
149°  Fah 

Under  the  action  of  boiling"  water,  the  starch 
granules  do  not  all  burst  at  once.     The  younger 


Action  of  Caustic  Alkalies  on  Starch.  41 


granules  are  the  first  to  be  acted  upon,  and,  as  the 
contact  with  the  boiling  water  is  continued  the  whole 
of  the  granules  undergo  gelatinisation. 

Action  of  Caustic  Soda  and  Potash  on 
Starch. — These  caustic  alkalies  have  a  peculiar 
action  on  starch.  If  starch  be  boiled  with  water 
containing  only  one-half  per  cent,  of  caustic  soda, 
a  paste  is  formed  which  is  much  thicker,  and  very 
much  more  adhesive,  than  if  boiled  with  water 
alone.  A  higher  percentage  of  the  alkali  produces 
a  still  Greater  adhesiveness.  These  substances  also 
tend  to  prevent  the  decomposition  of  the  starch 
paste,  especially  farina  paste  ;  the  acids,  which  are 
formed  by  this  decomposition,  are  immediately 
neutralised  by  the  alkali.  This  has  the  effect  of 
preventing  the  development  of  mildew  to  a  great 
extent.  Why  caustic  soda  prevents  the  decomposition 
of  farina  paste  is  not  known.  Whether  it  be  due 
to  the  actual  combination  of  the  alkali  with  the 
starch  compound,  or  whether  it  be  due  to  the  alkali 
retarding  the  formation  of  organic  acids  produced 
by  bacterial  action,  or  whether  by  its  presence  in 
the  caustic  state,  it  prevents  bacterial  action,  the 
authors  are  not  prepared  to  say,  but  they  believe 
that  the  whole  of  these  conditions  play  a  part  in  it. 

If  starch  be  treated  with  a  cold  concentrated 
solution  of  caustic  soda,  it  swells  out,  forming  a 
paste  of  great  tenacity,  resembling  in  appearance  a 
mass  of  gluten,  such  as  may  be  obtained  from  good 


42        The  Chemistry  and  Practice  of  Sizing. 


wheaten  flour.  The  starch,  so  treated,  does  not  lose 
much  of  its  increased  adhesiveness  on  boiling,  even 
when  the  alkali  is  previously  neutralised  with  acids. 
Whilst  cold  the  neutralised  starch  is  converted  into 
a  thin  liquid,  but  on  boiling,  it  is  found  to  be  nearly  as 
tenacious  as  it  was  before. 

Advantage  has  been  taken  of  this  action  of 
caustic  soda  and  potash  on  starch  to  place  upon  the 
market  many  substances  for  sizing  purposes.  These 
are  generally  starch  boiled  with  water  and  caustic 
soda,  or  starch  treated  with  concentrated  caustic  soda 
in  the  cold.  In  some  cases  they  take  the  form  of  a 
highly  glutenous-looking  mass,  consisting  of  starch 
and  caustic  soda.  In  other  cases,  two  liquids  are  sold, 
one  being  a  solution  of  caustic  soda,  and  the  other 
a  mineral  acid,  generally  sulphuric.  These  are  made 
of  such  a  strength  as  to  nearly  neutralise  each  other; 
the  caustic  soda,  which  must  be  in  slight  excess, 
TwTaddelling  about  70°,  and  the  sulphuric  acid 
Twaddelling  about  44°.  The  former  containing 
approximately  28  per  cent,  of  NaHO,  and  the  latter 
30  per  cent.  H2S04. 

Another  preparation  consists  of  soap  and  water,  to 
which  an  excess  of  caustic  soda  has  been  added.  The 
value  of  this  product  for  sizing  purposes  is  represented 
by  the  amount  of  free  caustic  soda  present  in  it. 

These  various  preparations  are  not  new,  one  of 
the  older  being  known  as  apparatine.  This  sub- 
stance will  be  further  discussed  later  in  this  chapter. 


Action  of  Acids  on  Starch. 


43 


Action  of  Acids  on  Starch. — When  starch 
and  water  are  boiled  with  weak  mineral  acids,  the 
starch  is  converted  first  into  dextrin,  and  finally  into 
glucose.  If  strong  sulphuric  acid  be  used,  carbon- 
isation quickly  takes  place,  whilst  strong  nitric  acid, 
under  similar  conditions,  converts  the  starch  into 
oxalic  acid.  In  the  cold,  however,  strong  sulphuric 
hydrochloric,  and  nitric  acid,  causes  the  starch  simply 
to  swell  out,  forming  a  paste. 

Tannic  acid  combines  with  starch,  precipitating 
it  from  solutions.  In  sufficient  quantity,  this  acid 
entirely  prevents  the  conversion  of  starch  into  dextrin 
and  maltose  by  means  of  diastase,    (see  page  47). 

The  organic  acids,  produced  by  the  fermentation 
of  starch  paste,  seem  to  have  the  power  of  converting 
the  starch  into  suger  when  boiled.  This  is  especially 
so  in  the  case  of  farina. 

Action  of  Calcium,  Magnesium,  and  Zinc 
Salts  on  Starch. — Starch  has  the  property  of 
combining  with  many  other  bases  besides  caustic 
soda  and  caustic  potash.  If  a  dilute  solution  of 
calcium  chloride  be  added  to  the  solution  formed 
by  boiling  starch  with  caustic  soda  and  water,  a 
double  decomposition  takes  place,  and  a  white 
insoluble  mass  is  formed,  which  is  a  compound  of 
calcium  and  starch.  The  starch  in  this  compound 
cannot  be  detected  by  iodine,  but  the  addition  of  an 
acid  liberates  the  starch,  which  may  then  be  detected 
by  iodine  in  the  usual  way. 


44        The  Chemistry  and  Practice  of  Sizing. 


Although  a  dilute  solution  of  chloride  of  calcium 
precipitates  starch  as  an  insoluble  compound,  it  is 
remarkable  that  if  starch  be  boiled  for  three  or  four 
hours  with  a  saturated  solution  of  this  substance, 
it  is  rendered  soluble,  and  when  the  solution  cools, 
it  sets  up  into  a  stiff  gummy  mass. 

A  strong  solution  of  chloride  of  zinc,  or  a  strong 
solution  of  chloride  of  magnesium,  when  boiled  with 
starch,  produces  a  somewhat  similar  result  to  that 
produced  by  chloride  of  calcium.  The  products 
obtained  by  this  treatment  are  much  more  adhesive 
than  starch  boiled  with  water,  and  this  has  been 
turned  to  account  by  many  manufacturers  of  sizing 
specialities.  This  matter  is  further  dealt  with  under 
soluble  starch. 

Starch  is  precipitated  from  solution  by  means  of 
a  solution  of  lime  (hydrate  of  calcium)  in  sugar 
syrup.  Solutions  of  hydrate  of  barium,  and  hydrate 
of  strontium  combine  with  starch  also,  producing 
insoluble  compounds,  in  which  the  starch  is  not 
detected  by  means  of  iodine  solution,  unless  the 
compounds  are  first  decomposed  by  means  of  an  acid. 

Magnesium  salts,  in  dilute  solution,  precipitate 
starch  from  solution  in  the  same  way  as  calcium  salts. 

Action  of  Borax  on  Starch  Paste. — When  a 
mixture  of  starch  and  water  is  heated  to  a  temperature 
sufficiently  high  to  gelatinise  the  starch  granules, 
it  forms  a  viscid  mass.  In  this  state  it  will  adhere 
to  almost  any  substance  with  which  it  may  come  in 


Action  of  Borax  on  Starch  Paste,  45 


contact,  and  it  may  be  spread  by  means  of  a  brush 
or  by  means  of  a  spatula.  But  it  a  small  quantity  of 
borax  be  added  to  the  starch  paste,  and  the  mixture 
kept  constantly  stirred  by  means  of  a  glass  rod 
for  a  short  time,  a  most  peculiar  effect  is  produced 
on  the  ruptured  starch  granules.  The  mass  first 
begins  to  thicken,  and  the  paste  becomes  less 
viscid,  until  it  finally  loses  its  power  of  adhering 
to  other  substances,  and  instead,  it  is  found  to  possess 
most  marked  powers  of  self-adhesiveness.  The 
mass  has  now  the  appearance  of  a  watery  jelly,  and 
it  may  be  rolled  in  the  hands  without  any  of  it  adhering 
to  them.  The  borax  seems  to  cause  a  coagulation 
similar  in  effect  to  that  produced  when  an  egg  is 
boiled.  Before  boiling,  the  white  of  the  egg  is  thin 
and  viscid,  whilst  after  boiling  it  is  thick,  and  the 
viscosity  has  disappeared. 

This  result  may  be  obtained  from  any  of  the 
starches,  when  treated  as  described  above,  but  it  is 
most  marked  in  the  case  of  farina.  An  experiment 
illustrating  this  peculiar  change  may  be  made  as 
follows  : — 

Mix  one  ounce  of  farina  with  six  ounces  of  water 
in  an  evaporating  basin,  and  heat  the  mixture  by 
means  of  the  Bunsen  s  flame,  or  better  by  means  of 
steam,  until  the  granules  burst.  The  source  of  heat 
is  then  removed  and  a  few  drops  of  solution  of  borax 
added,  The  mixture  is  kept  well  stirred,  and  in  a 
few  minutes  it  will  be  seen  that  it  is  losing  its 


46        The  Chemistry  and  Practice  of  Sizing. 


viscosity,  and,  instead  of  adhering  to  the  sides  of 
the  basin,  it  clings  together  in  a  tenacious  jelly-like 
mass,  which  can  be  lifted  bodily  from  the  basin. 
This  mass  may  be  rolled  between  the  hands 
without  adhering  to  them,  and  what  is  more  re- 
markable, without  showing  any  apparent  "wetness." 
If  the  jelly-like  mass  be  placed  on  blotting  paper, 
the  paper  does  not  become  damp.  It  has,  in  fact, 
lost  all  the  physical  characteristics  of  starch  paste. 
If  a  ball  of  this  jelly-like  mass  be  left  for  a  few7 
days,  it  either  dries  up  into  a  hard  crystalline  looking 
mass,  or  else  the  water  separates  out  from  it  bodily, 
leaving  the  starch  behind. 

This  action  of  borax  on  starch  paste  is  peculiar 
and  interesting.  It  was  discovered  by  the  authors 
whilst  experimenting  with  a  view  to  finding  out  the 
action  of  different  substances  on  the  various  starches. 
Whether  it  can  ever  be  turned  to  practical  use  for 
sizing,  or  for  any  other  purpose,  is  a  matter  which 
requires  further  investigation.  Borax  has  been  used 
for  many  years  in  conjunction  with  starch  for  giving 
a  gloss  to  linen,  and,  as  a  matter  of  fact,  borax  is  the 
basis  of  most  of  the  so-called  starch  glosses. 
Whether  the  glossing  effect  is  due  to  the  hot  iron, 
which  is  used  in  the  glossing  process,  breaking  up, 
or  gelatinising  the  starch,  and  thus  making  it  sus- 
ceptible to  the  action  of  the  borax,  in  the 
same  manner  in  which  starch  paste  is  acted  upon 
by  borax,  the  authors  are  not  prepared  to  say,  but 


Action  of  Bacteria  on  Starch. 


47 


they  think  that  this  is  probably  the  action  which 
takes  place. 

Action  of  Diastase  on  Starch. — Diastase, 
the  active  principle  of  malted  grain,  has  the  power 
of  decomposing  starch,  in  the  presence  of  water, 
at  a  temperature  of  140°  to  160°  Fah.,  forming 
dextrin  and  maltose. 
3C„H10O6    +    H20    -    C6HX0O5     +  C12H2201X. 

Starch.  Water.  Dextrin.  Maltose. 

This  action  of  diastase  is  turned  to  practical  use 
by  the  bleacher  and  finisher  when  it  is  necessary  to 
remove  the  starch  from  goods  which  have  been 
wrongly  finished,  and  where  it  is  not  desirable  to 
send  them  through  the  bleaching  process  again.  For 
this  purpose  diastase,  in  the  form  of  ground  malt, 
is  used.  The  cloth  is  steeped  for  a  few  hours 
in  a  solution  of  malt,  at  a  temperature  of  140°  Fah., 
and  in  that  time,  the  insoluble  starch  is  converted 
into  soluble  dextrin  and  maltose,  which  may  be 
readily  washed  out  by  boiling  in  water.  The  action 
of  diastase  on  starch  is  further  discussed  under 
soluble  starch. 

Action  of  Bacteria  on  Starch. — Starch  pastes, 
produced  by  boiling  starch  with  water,  are  more  or 
less  liable  to  decomposition  by  the  action  of  bacteria. 
Some  starches  show  a  much  greater  tendency  to 
decompose  from  this  cause  than  others.  Farina  and 
tapioca  are  particularly  liable  to  this  process  of  de- 
composition and  it  is  certainly  curious  that  this 


48        The  Chemistry  and  Practice  of  Sizing. 


action  should  be  most  pronounced  in  starches 
obtained  from  roots  and  tubers,  and  which  of 
necessity,  have  been  developed  underground.  It  is 
highly  probable  that  close  contact  with  the  soil, 
highly  charged  with  nitrogenous  matter,  may  be  the 
cause  of  this  tendency  to  decomposition.  Starches 
obtained  from  seeds,  and  from  the  pith  of  plants, 
are  not  so  subject  to  decomposition. 

The  products  of  decomposition,  brought  about 
by  bacterial  action,  are  chiefly  dextrin,  glucose, 
carbon  dioxide,  ethyl  and  amyl  alcohols,  and  acetic 
and  butyric  acids.  Villiers  found  that  the  addition  of  a 
pure  cultivation  of  Bacillus  amylobacter  to  a  5  per 
cent,  starch  paste  causes  complete  liquefaction  in  24 
hours,  and  on  allowing  the  fermentation  to  continue 
some  time,  the  liquid  no  longer  gave  a  blue  coloura- 
tion with  iodine.  The  products  of  the  change  in 
this  case  were  entirely  dextrins,  neither  maltose  nor 
dextrose  being  found  to  be  present.  This  shows 
that  this  particular  organism  converts  starch  directly 
into  dextrin  without  the  intervention  of  any  diastase 
secreted  by  the  ferment.  This  matter  is  further 
discussed  under  farina. 

Identification  of  the  Various  Starches. 

Thevarious  starches  canbe identified  onlybymeans 
of  the  microscope,  and  this  most  valuable  instrument 
should  be  in  the  hands  of  every  manufacturer, 


Microscopical  Appearance  of  Starch  Granules,  49 

The  starches  are  prepared  for  examination 
as  follows  : — A  small  quantity  of  the  sample  is 
thoroughly  rubbed  up  with  water  in  a  watch  glass, 
by  means  of  a  glass  rod.  A  drop  of  the  milky  fluid 
is  then  placed  on  the  centre  of  a  glass  slide,  and  a 
thin  cover  glass  placed  over  it.  Any  excess  of 
liquid  is  removed  from  the  edges  of  the  cover  by 
means  of  blotting  paper.  The  slide  is  then  placed 
on  the  stage  of  the  microscope,  the  body  of  which  is 
brought  down  carefully  by  means  of  the  large  ad- 
justing screw,  until  the  granules  of  starch  are  visible, 
the  exact  focus  being  obtained  by  careful  adjustment 
with  the  fine  screw.  The  granules  of  the  various 
starches  differ  considerably  in  size  and  shape,  and 
very  little  practice  is  necessary  to  enable  the  operator 
to  readily  distinguish  all  those  which  come  under 
the  notice  of  the  sizer,  whether  examined  separately 
or  in  mixtures. 

An  illustration,  showing  the  microscopical  appear- 
ance of  the  most  important  starch  granules,  is  given 
on  plate  i  The  following  description  enumerates 
their  characteristic  features  :  — 

Wheaten  Starch. — The  granules  of  wheaten 
starch  vary  considerably  in  size.  The  smaller  ones 
are  generally  round,  and  they  are  provided  with  a 
dark  central  spot  or  hilum,  which,  however,  requires 
a  power  of  460  diameters  to  distinguish.  The  large 
granules  are  more  or  less  rounded,  and  marked  with 
concentric  rings.    The  small  wheaten  starch  granules 

D 


50       The  Chemistry  and  Practice  of  Sizing. 


might  be  mistaken  for  rice  starch  by  the  novice,  but 
they  are  seen  to  be  very  different  if  carefully 
examined  ;  those  of  wheaten  starch  being  round, 
whilst  rice  starch  granules  are  angular. 

A  comparison  should  be  made  by  making  up 
three  slides,  and  examining  one  after  the  other.  The 
first  should  be  pure  wheaten  starch,  the  second  pure 
rice  starch,  and  the  third  a  mixture  of  the  two. 

Matze  or  Corn  Starch. — This  starch  is  readily 
identified  under  the  microscope.  The  granules 
are  very  even  in  size,  and  they  present  the  appear- 
ance of  having  been  originally  rounded,  but  by 
contact,  and  probably  by  pressure,  the  edges  have 
become  flattened,  thus  giving  them  a  polyhedral 
form.  The  majority  of  the  granules  have  a  star- 
shaped  appearance  in  the  centre  when  viewed  under 
the  microscope.  Sometimes  this  takes  more  the 
form  of  a  \, 

Maize  starch  granules  are  smaller  than  the  larger 
wheaten  starch  granules. 

Farina  or  Potato  Starch. — The  granules  of 
this  starch  are  larger  than  those  of  any  other  starch 
used  for  sizing.  They  are  oval  in  shape  and 
are  marked,  in  many  cases,  but  not  always,  with  con- 
centric rings.  The  appearance  of  this  starch  under 
the  microscope  is  an  important  indication  of  its  quality. 
In  good  samples  of  farina  the  granules  are  of  an 
even  size,  whilst  in  inferior  samples  the  granules  are 
very  irregular  in  size,  and  very  often  the  larger 


THE  STARCHES 


MICROSCOPIC  APPEARANCE  OF  STARCH  GRANULES. 

Plate  I. 


Microscopical  Appearance  of  Starch  Granules.  51 

granules  are  more  or  less  frayed  at  the  edges.  This 
matter  is  further  dealt  with  in  the  section  devoted 
to  farina. 

Sago  Starch. — The  chief  characteristic  of  the 
granules  of  this  starch  is  the  flattened  end  of  each 
granule.  The  granules  are  smaller  than  farina 
granules,  and  they  are  more  irregular  in  shape. 
Many  are  ovate,  whilst  others  are  more  rounded  and 
show  irregular  protuberances,  not  unlike  those  seen 
in  certain  potatoes.  The  surface  of  the  sago 
granules,  as  seen  under  the  microscope,  is  character- 
ised by  a  number  of  peculiar  markings, 

Rice  Starch. — The  granules  of  this  starch  are 
amongst  the  smallest  known,  their  polyhedral  shape 
rendering  them  easy  of  detection.  When  rice  flour, 
or  ground  rice,  is  under  examination,  it  is  necessary  to 
grind  it  in  water  for  some  little  time,  in  order  to  bring 
about  a  separation  of  the  starch  from  the  gluten. 

Tapioca  Starch, — The  granules  of  this  starch 
vary  more  in  appearance  than  those  of  any  of  the 
other  starches  used  in  sizing.  This  is  probably  due 
to  the  fact  that  the  tapioca  of  commerce  is  obtained 
from  a  variety  of  plants,  Tapioca  granules  are  about 
thesame  sizeas  maize  granules,  but  they  are  altogether 
different  in  appearance.  In  some  cases  the  granules 
are  perfectly  round  and  show  a  central  dot  or  hilum, 
whilst  in  other  cases  the  granules  are  D  shaped.  In 
any  case  tapioca  is  readily  distinguised  from  those 
starches  already  described. 


52        The  Chemistry  and  Practice  of  Sizing. 


WHEATEN  FLOUR. 

Wheaten  flour  is  the  most  important  of  all  the 
substances  used  for  giving  adhesive  property  to  size. 
It  is  a  complex  substance  containing  a  number  of 
organic  bodies,  themostimportantof  which  are  starch, 
gluten,  albumen,  sugar,  dextrin,  and  cellulose.  There 
is  also  present  a  small  quantity  of  mineral  matter. 

The  value  of  a  sample  of  wheaten  flour  for 
sizing  purposes  depends  upon  the  proportion  and  the 
quality  of  the  starch  and  gluten  contained  therein. 
It  is  therefore  necessary  that  care  should  be  exer- 
cised in  its  selection. 

Before  describing  the  tests  which  should  be 
applied  to  wheaten  flour  it  will  be  advisable  to 
describe  the  various  substances  found  present  in  it. 

Cellulose, — This  substance  resembles  the  fibre 
of  wood.  An  example  of  cellulose,  but  a  modifica- 
tion of  the  kind  found  in  flour,  is  ordinary  cotton. 

Gluten. — Gluten  is  a  powerfully  adhesive  sub- 
stance found  in  wheaten  and  other  flours.  It  may 
be  readily  separated  from  wheaten  flour  by  knead- 
ing a  portion  of  flour  with  a  little  water.  The 
dough  produced  is  placed  in  a  bag  of  silk,  or  fine 
linen,  and  gently  pressed  in  contact  with  a  stream 
of  running  water.  By  this  treatment  the  whole  of 
the  starch,  and  the  soluble  matters  of  the  flour,  are 
washed  away, and  there  remains  behind  a  sticky  mass 
which  is  very  rich  in  nitrogen.    This  crude  gluten 


Wheaten  Flour. 


53 


consists  chiefly  of  gluten-fibrin,  glutin,  and  mucedin, 
with  small  quantities  of  fat  and  mineral  matter. 

Albumen.  —  This  nitrogenous  substance  is 
indentical  with  the  albumen  found  in  animals.  The 
white  of  an  egg  may  be  taken  as  representing  almost 
pure  albumen.  The  albumen  of  flour  is  soluble  in 
cold  water,  and  it  is  coagulated,  and  precipitated, 
when  the  solution  is  boiled. 

Dextrin. — This  substance  is  always  found  in 
flour.  It  is  soluble  in  cold  water,  and  may  be 
separated  from  the  other  constituents  of  flour  by 
digesting  a  small  quantity  of  flour  with  water.  The 
liquid  is  filtered  off,  boiled  to  coagulate  the  albumen, 
and  again  filtered.  The  solution  thus  obtained  will 
contain  the  dextrin  and  the  sugar  present  in  the  flour. 
The  presence  of  dextrin  is  ascertained  by  its  reaction 
with  iodine  solution.  Iodine  imparts  a  reddish 
purple  colour  to  the  solution  containing  dextrin. 

Sugar. — This  substance  is  a  natural  constituent 
of  flour.  It  occurs  in  the  form  known  as  glucose  or 
grape  sugar,  a  form  which  differs  somewhat  in 
chemical  and  physical  properties  from  ordinary  cane 
or  crystallisable  sugar. 

Starch. — This  most  essential  constituent  of 
wheaten  flour  has  been  fully  dealt  with  already. 

Mineral  Matter. — This  is  found  in  all  flours. 
It  is  left  as  ash  when  the  flour  is  burned,  and  it  is 
composed  principally  of  potash  and  phosphoric  acid, 
with  smaller  proportions  of  soda,  lime,  magnesia  and 


54        The  Chemistry  and  Practice  of  Sizing. 


iron  oxide,  in  combination  with  sulphuric,  carbonic, 
and  silicic  acids,  and  chlorine. 

Bran. — This  is  the  cortical  part  of  the  grain. 
It  is  sometimes  found  in  flour  through  imperfect 
dressing. 

Water. — This  is  an  essential  constituent  of  all 
vegetables.  The  average  amount  found  in  wheaten 
flour  is  about  13  per  cent. 

It  would  be  a  great  advantage  to  the  sizer  if  he 
knew  the  composition  of  each  consignment  of  flour 
he  used  in  his  mixings,  as  it  would  ensure  greater 
uniformity  in  his  results,  but  the  time  occupied  in 
making  a  full  analysis  puts  it  beyond  his  reach  in 
most  cases.  It  is  possible,  however,  to  apply  many 
simple  tests,  particulars  of  which  are  given  herewith ,  to 
determine  the  quality  of  a  flour  for  sizing  purposes, 
and  these  tests,  if  carefully  carried  out  and  the 
results  recorded,  would  prove  of  great  utility,  and 
lead  to  greater  uniformity  in  the  results  obtained  in 
sizing. 

Determination  of  the  Value  of  Wheaten 
Flour  for  Sizing  Purposes. 

Colour. — Flour  should  not  be  dark  in  colour. 
The  whiter  the  flour  the  less  chance  it  has  of 
affecting  the  colour  of  the  woven  cloth.  The  test 
for  colour  should  be  made  by  comparison  with  a 
" standard"  flour.    A  good  sample  as  regards  colour 


Consistency  of  Flour  Paste. 


55 


should  be  kept  for  this  purpose.  The  test  is  made 
by  placing  a  little  of  the  sample  under  examination 
by  the  side  of  the  "standard"  sample  on  a  sheet  of 
blue  paper.  On  pressing  them  flat  with  a  knife  any 
difference  in  shade  is  readily  seen  at  the  point  of 
contact. 

A  further  test  should  always  be  made  by  boiling 
the  same  quantities  of  the  samples  with  water,  the 
proportions  being  the  same  as  given  in  the  test  for 
consistency.  Some  samples  of  flour  alter  in  colour 
to  an  appreciable  extent  when  boiled. 

Consistency  of  Flour  Paste. — The  value  of  a 
pure  wheaten  flour  for  sizing  purposes  may  be  judged 
by  the  "stiffness"  of  the  paste  produced  by  boiling 
a  definite  weight  of  flour  with  a  definite  measure  of 
water,  and  comparing  it  with  the  "standard"  treated 
in  the  same  way.  For  this  purpose  the  authors  use 
10  grammes  of  flour  and  100  cubic  centimetres  of 
water,  or  i  ounce  of  flour  to  10  ounces  of  water. 

The  samples  of  flour  are  placed  in  small  cylin- 
drical beakers,  and  the  water  is  added  from  a  100  c.c. 
pipette,  or  it  is  carefully  measured  in  a  suitable  glass 
measure.  The  mixture  is  carefully  stirred  with  a 
glass  rod  in  order  to  thoroughly  break  up  the 
particles  of  flour,  thus  getting  an  even  mixture  free 
from  lumps.  The  beakers  are  then  placed  in  a 
vessel  containing  water,  which  is  heated  by  means 
of  a  Bunsen's  flame,  the  contents  being  kept 
constantly  stirred  during  the  whole  process. 


56        The  Chemistry  and  Practice  of  Sizing. 


The  most  suitable  vessel  for  heating  the  flour  is 
an  iron  pan  to  which  is  fitted  a  brass  or  copper  disc 
in  which  four  or  five  circular  holes,  sufficiently 
large  to  pass  the  beakers  through,  have  been 
cut.  The  beakers  are  supported  on  the  disc  by 
their  rims.  The  disc  should  be  mounted  on  supports 
so  as  to  prevent  the  bottoms  of  the  beakers  touching 
the  bottom  of  the  pan.  By  using  an  apparatus  such 
as  described  above  an  accurate  comparison  of 
several  samples  may  be  made  at  the  same  time,  as 
the  samples  are  heated  under  identical  conditions. 
It  is  advisable  to  heat  the  samples  for  15  minutes, 
and  the  water  in  the  pan  should  be  boiling  before 
they  are  placed  in  it.  If  more  than  two  samples  are 
being  examined  it  will,  of  course,  be  necessary  to 
have  assistance  in  the  stirring  until  the  granules  of 
starch  burst,  afterwards  they  may  be  stirred  alter- 
nately. The  advantages  of  the  above  method  are 
that  the  same  amount  of  evaporation  of  the  water 
mixed  with  the  flour  or  starch  takes  place,  and 
there  is  not  the  same  liability  of  error  as  there 
would  be  if  separate  samples  were  boiled  for  a 
definite  time. 

After  the  contents  of  the  beakers  have  been 
heated  for  the  specified  time  they  are  removed  from 
the  pan  and  allowed  to  cool  for  twelve  hours.  They 
may  then  be  examined  for  consistency  and  colour. 
Any  variation  in  consistency  may  be  readily  judged 
by  pressing  the  fingers  into  each  sample  of  paste. 


Bleaching  of  Wheaten  Flour.  57 


N.B. — It  is  important  to  remember  that  the  fore- 
going tests  are  of  value  only  when  comparing  pwe 
samples  of  wheaten  flours.  The  tests  become  worth- 
less if  any  of  the  samples  under  examination  are 
mixtures  containing  maize  starch.  This  starch  is 
much  whiter  than  wheaten  flour,  and  it  gives  a  thicker 
paste.  It  will,  therefore,  be  readily  seen  how  the  sizer 
may  be  misled  in  his  estimation  of  the  value  of  a  flour 
unless  he  has  previously  determined  its  purity.  It 
would  be  quite  possible  for  him  to  select  a  poor  flour 
mixed  with  maize  starch  if  he  depended  upon  the 
colour,  and  the  consistency  of  the  paste  obtained  by 
boiling  the  sample  with  water.  But  if  he  bases  his 
opinion  on  the  whole  of  the  tests  given  for  flour, 
especially  as  regards  the  quality  of  the  gluten,  he  can- 
not get  far  wrong.  The  authors  would  strongly  urge 
upon  manufacturers  the  desirability  of  having  nothing 
to  do  with  wheaten  flours  mixed  with  other  starches. 
If  it  be  necessary  to  improve  the  colour  it  will  be 
far  better  if  he  mixes  the  requisite  amount  of  maize 
starch  with  it  himself. 

Another  point  to  remember  is  that,  within 
recent  years,  it  has  become  a  fairly  common 
practice  to  subject  dark  coloured  low  grade  flours 
to  a  bleaching  operation.  It  does  not  therefore 
follow  that  whiteness  is  an  indication  of  high 
quality. 

Estimation  of  Moisture.  —  It  is  very  necessary 
that  the  amount  of  moisture  present  in  a  sample 


58        The  Chemistry  and  Practice  of  Sizing. 


of  flour  should  be  estimated.  The  method  of  pro- 
cedure is  described  on  pages  22  and  23. 

Estimation  of  Gluten. — In  order  to  determine 
the  proportion  of  gluten  in  a  sample  of  flour,  exactly 
10  grammes  should  be  weighed,  and  transferred  to 
a  porcelain  mortar.  A  sufficient  quantity  of  water 
is  then  added  and  the  mixture  is  kneaded  into  a 
dough  by  the  aid  of  the  pestle.  Care  must  be  taken 
not  to  use  more  water  than  is  necessary  to  produce 
a  dough  which  should  leave  the  mortar  without  leav- 
ing- a  trace  behind.  The  dough  should  be  allowed 
to  stand,  in  every  case,  for  half-an-hour.  It  is  then 
transferred  to  a  fine  linen  or  silk  cloth,  which  has 
been  previously  wetted  with  water,  and  tied  up  in 
such  a  way  as  to  form  a  bag.  This  is  gently  pressed 
with  the  fingers  in  a  stream  of  running  water,  in 
order  to  wash  away  the  starch. 

A  portion  of  the  milky  fluid  should  be  collected 
in  a  suitable  vessel  for  the  microscopical  examina- 
tion previously  described  on  page  49. 

The  washing  must  be  continued  until  the  water 
begins  to  run  away  clear.  The  bag  is  then  opened 
and  the  gluten  examined.  Gluten  from  a  good 
sound  flour  is  found  self-adherent,  in  an  elastic  mass* 
whilst  gluten  from  an  unsound  or  weak  flour  will  be 
found  in  the  form  of  little  pellets,  having  no  tend- 
ency to  adhere  in  a  single  mass.  Occasionally,  where 
the  gluten  is  very  weak,  it  will  pass  through 
the  cloth,  and  will  be  found  adhering  to  the  outside. 


Estimation  of  Gluten. 


59 


The  gluten  should  be  removed  from  the  cloth, 
and  thoroughly  washed  in  a  stream  of  running 
water,  by  holding  it  in  the  ball  of  one  hand,  and 
kneadine  it  with  the  fingers  of  the  other  hand,  until 
the  washings  show  no  sign  of  starch.  This  point  is 
readily  determined  by  squeezing  the  water  from  the 
wet  gluten  into  a  beaker  full  of  clear  water.  If  all 
the  starch  has  been  removed,  the  water  in  the 
beaker  will  remain  clear,  whereas  it  will  be  rendered 
turbid  if  starch  be  present.  In  the  latter  case  the 
washing  must  be  continued. 

Sometimes  the  gluten  will  be  found  to  be 
covered  with  granular  particles.  This  may  be  due 
to  the  flour  having  been  adulterated  wTith  rice  or 
maize  flour,  or  it  may  be  due  to  some  portion  of 
the  flour  not  having  been  properly  ground.  These 
gritty  granular  particles  should  be  washed  from  the 
gluten  into  a  suitable  vessel,  and  examined  separately 
under  the  microscope. 

The  gluten  may  be  weighed  either  as  moist  or 
dry  gluten.  If  weighed  as  moist  gluten  the  mass 
should  be  rolled  between  the  dry  palms  of  the  hands 
until  it  begins  to  stick  slightly  to  them.  The 
moisture  is  evaporated  by  the  warmth  of  the  hands. 
The  gluten  is  then  quickly  placed  upon  a  tared  watch 
glass  and  the  whole  weighed.  The  weight  of  the 
watch  glass,  deducted  from  the  total  weight,  gives  the 
amount  of  moist  gluten, and  thismultiplied by  iogives 
the  percentage  of  moist  gluten  present  in  the  sample. 


6o       The  Chemistry  and  Practice  of  Sizing. 

It  is  preferable  to  determine  the  amount  of  the 
gluten  both  in  the  moist  and  the  dried  state,  and 
when  this  is  done  it  is  advisable  to  perform  the 
weighings  on  a  small  thin  sheet  of  tinned  iron  kept 
for  the  purpose,  instead  of  on  a  watch  glass.  This 
is  because  the  gluten  is  so  powerfully  adhesive  that  it 
will  pull  pieces  out  of  the  glass  as  it  contracts  on  drying. 

In  determining  the  amount  of  both  moist  and  dry 
gluten,  the  moist  gluten  is  first  weighed.  The  plate 
containing  it  is  then  placed  in  the  steam  or  air  oven, 
until  the  weight,  after  cooling  in  the  desiccator, 
remains  constant,  This  weight,  multiplied  by  10, 
gives  the  percentage  of  dry  gluten. 

The  percentage  of  dry  gluten  may  be  calculated 
from  the  percentage  of  moist  gluten  by  dividing  the 
latter  by  2*61.  This  calculation  may  be  used  as  a 
check  on  the  accuracy  of  the  estimation  where  both 
moist  and  dry  gluten  is  determined. 

Gluten,  when  of  good  quality,  is  a  powerfully 
adhesive  substance,  and  flour  containing  a  moderately 
high  percentage  of  it  is  useful  in  fixing  China  clay 
on  the  yarn. 

Wheaten  flours  vary  very  considerably  in  the 
amount  and  quality  of  gluten  contained  in  them, 
and,  as  a  rule,  the  value  of  a  flour  for  sizing  purposes 
is  based  on  these  points.  There  is  no  doubt  that 
the  quantity,  and  more  especially  the  quality,  of 
gluten  are  most  important  factors  in  determining  the 
value  of  a  sizing  flour,  as  it  invariably  follows  that 


Wheaten  Flour. — Detection  of  Adulterations.  61 

where  the  gluten  is  high  in  quality  the  starch  present 
in  the  sample  is  well  matured  and  strong. 

The  amount  of  moist  gluten  found  by  the  authors 
in  the  examination  of  many  samples  of  sizing  flours 
varies  from  5*14  per  cent,  in  very  poor  samples,  to 
39  per  cent,  in  very  good  ones.  The  latter  figure 
represents  nearly  15  per  cent,  of  dry  gluten  and 
the  former  nearly  2  per  cent. 

Sizers  differ  very  greatly  in  their  opinion  as  to 
the  value  of  gluten  for  sizing  purposes.  Many 
contend  that  a  flour  containing  a  high  percentage  of 
gluten  is  the  best,  whilst  others  maintain  that  a  flour 
containing  a  medium  percentage  of  this  substance  is 
the  more  valuable.  If  it  were  a  question  of  food, 
then  there  can  be  no  doubt  that  a  high  percentage 
of  gluten  in  a  flour  would  be  advantageous,  but  for 
sizing  purposes  it  is  not  so  necessary  that  the  gluten 
should  be  present  in  very  large  quantities  so  much 
as  that  it  should  be  sound  and  strong.  The  authors 
recommend  a  flour  containing  from  9  to  12  percent, 
of  dry  gluten,  providing  the  gluten  is  of  high  quality. 
As  a  matter  of  fact  a  great  deals  depends  also  upon 
the  treatment  to  which  the  flour  is  to  be  subjected 
previous  to  its  being  made  into  size.  This  matter 
will  be  discussed  when  dealing  with  the  fermentation 
of  flour. 

Mineral  Matter  or  Ash. — Flour  free  from 
adulteration  contains  from  07%  to  o*8%  of  ash. 
Anything  above  1%  should  be  looked  upon  with 


62        The  Chemistry  and  Practice  of  Sizing, 


suspicion.  In  determining  the  question  of  mineral 
adulteration  it  is  only  necessary  for  the  sizer  to  know 
that  his  flour  does  not  contain  an  excess  of  mineral 
matter.  To  obtain  this  information  a  known  weight 
of  flour  should  be  burnt  in  a  platinum  or  porcelain 
crucible,  the  resultant  ash  carefully  weighed,  and 
calculated  to  a  percentage.  The  method  of  procedure 
is  as  follows: — A  crucible  with  a  lid  is  heated  in  the 
Bunsen's  flame,  and  then  allowed  to  cool  in  the 
desiccator.  When  cold  it  is  carefully  weighed  on 
the  balance,  and  the  weight  noted.  About  two 
grammes  of  flour  should  be  placed  in  the  crucible 
and  the  whole  weighed  again.  The  difference  in 
the  first  and  second  weighings  gives  the  amount  of 
flour  taken.  The  crucible,  with  its  contents,  is 
placed  on  a  triangle,  supported  on  a  tripod  stand. 
Heat  is  applied  by  means  of  a  Bunsen's  flame.  The 
flour  is  quickly  converted  into  a  hard  mass  of 
charcoal,  which,  on  continuing  the  heating  for  an 
hour  or  two,  is  burnt  away,  leaving  a  white  or  grey 
ash.  At  this  point  the  lid  of  the  crucible  is  put  on, 
the  whole  allowed  to  cool  in  the  desiccator,  and  then 
weighed.  The  weight  of  the  lid  and  crucible 
deducted  from  the  total  weight,  gives  the  amount 
of  ash,  and  this  should  be  calculated  to  a  percentage 
in  the  usual  way. 

Another  way  of  roughly  estimating  the  amount 
of  mineral  matter  present  in  a  sample  of  flour  or 
starch,  is  to  make  a  comparative  test  as  follows: — 


Wheat  en  Flour. — Detection  of  Adulterations.  63 

A  small  thimble-full  of  flour  of  known  purity  is 
placed  in  a  long  narrow  test  tube.  The  tube  is  half 
filled  with  chloroform  and  well  shaken.  The  same 
quantity  of  the  sample  to  be  tested  is  placed 
in  a  similar  tube,  with  the  same  quantity  of 
chloroform  and  well  shaken.  The  two  samples  are 
allowed  to  stand  for  about  six  hours,  after  which 
they  are  compared.  Pure  flour  or  starch  will  float 
on  the  surface  of  the  chloroform,  this  liquid  being 
much  heavier  than  flour,  whilst  mineral  matters, 
such  as  China  clay  or  plaster  of  Paris,  will  sink  to 
the  bottom  of  the  test  tube.  A  comparison  of  the 
two  test  tubes  will  show  whether  there  is  any 
adulteration  of  the  sample  under  examination. 

Adulteration  with  other  Starches. — Wheaten 
flour  is  frequently  mixed  with  other  starches.  Some- 
times this  is  done  simply  for  the  sake  of  extra  profit 
and  sometimes  it  is  done  by  dealers  who  make  a 
special  sizing  flour.  In  any  case  it  is  important  that 
the  sizer  should  know  the  constituents  of  the  flour 
he  is  using,  otherwise  he  becomes  dependent  upon 
one  dealer  for  his  flour,  or  else  he  may  get  results 
he  is  not  expecting  if  he  changes  his  source  of  supply. 

The  various  starches  used  for  admixture  with 
flour  may  be  detected  by  means  of  the  microscope 
in  the  manner  already  described.  The  starches  most 
likely  to  be  found  as  adulterants  in  wheaten  flour 
are  rice  and  maize  flours,  maize  starch,  and  tapioca. 
The  market  price  of  the  starches  of  course  governs 


64        The  Chemistry  and  Practice  of  Sizing. 


the  particular  one  which  is  used  for  the  purpose  of 
adulteration  at  the  moment. 

The  microscopic  appearance  of  wheaten  starch 
is  a  very  valuable  indication  of  its  value  for  sizing 
purposes.  It  will  be  invariably  found  that  a  flour 
composed  of  well  developed  granules  is  a  stronger 
flour  than  one  in  which  there  are  a  very  large 
number  of  the  smaller  granules.  This  is  a  point 
never  mentioned  in  books  dealing  with  flour  for 
sizing  purposes,  but  it  is  one  which  experience 
has  shown  to  be  of  the  greatest  importance. 

Analysis  of  Wheaten  Flour. 

A  full  analysis  of  flour  is  too  long  and  tedious 
an  operation  as  a  rule  for  a  manufacturer  to  attempt, 
but  it  is  necessary  to  detail  the  process  for  the 
guidance  of  those  students  who  wish  to  go  fully  into 
the  matter. 

The  following  will  be  found  to  be  a  useful  method 
of  procedure : — 

(1)  Moisture. — This  is  determined  by  drying 
three  or  four  grammes  in  the  water  oven  until  the 
sample  ceases  to  lose  weight,  as  described  on  pages 
22  and  23.   The  water  is  calculated  to  a  percentage. 

(2)  Ash. — This  is  determined  by  carefully  burn- 
ing from  one  to  two  grammes  of  flour  in  a  platinum 
crucible,  as  described  on  pages  61  and  62,  and,  after 
weighing  the  residue,  calculating  to  a  percentage  of 
the  flour  taken. 


Analyses  of  Flour. 


65 


(3)  Gluten. — This  is  determined  by  washing, 
as  described  on  page  57,  et  seq.,  and  weighing  as  dry 
gluten.  The  amount  found  is  calculated  to  a 
percentage  of  the  flour  taken. 

(4)  Soluble  Albuminoids,  Glucose  and  Dex- 
trin.— The  following  method  may  be  used 
for  estimating  the  soluble  albuminoids,  etc., 
in  flour. — 10  grammes  of  flour  are  treated  with 
40  cubic  centimeters  of  cold  water.  The  mixture  is 
allowed  to  stand  for  exactly  one  hour.  The  liquid 
is  then  passed  through  a  dry  filter,  and  after  allowing 
the  first  portions  to  run  away,  the  rest  of  the  liquid 
is  collected  and  examined  as  follows: — 20  cubic 
centimeters  of  the  filtrate  (=5  grammes  of  flour) 
should  then  be  collected  and  treated  with  an  equal 
volume  of  methylated  spirit.  By  this  treatment  the 
soluble  albuminoids  are  precipitated,  the  amount  of 
which  will  depend  upon  the  quality  of  the  flour,  the 
best  samples  giving  the  least  quantity  of  precipitate. 
The  albumen  is  filtered  out  and  the  liquid  is  collected 
in  a  weighed  evaporating  basin.  The  precipitate  is 
carefully  washed  with  water,  and  the  washings  are 
added  to  the  contents  of  the  basin.  The  filtrate  and 
washings  are  then  evaporated  to  dryness  on  the 
water  bath,  afterwards  heated  in  the  drying  oven, 
and  then  weighed.  The  weight  obtained  deducted 
from  the  weight  of  the  basin,  gives  the  total  weight 
of  sugar  and  dextrin  in  5  grammes  of  flour,  and 
this  multiplied  by  20  gives  the  percentage. 


66        The  Chemistry  and  Practice  of  Sizing. 


Soluble  Albuminoids. — The  amount  of  soluble 
albuminoids  should  be  determined  as  follows: — 10 
cubic  centimeters  of  the  original  filtrate  should  be 
evaporated  to  dryness,  as  previously  described,  in  a 
tared  evaporating  basin.  The  weight  obtained  gives 
the  total  soluble  albuminoids,  sugar,  etc.,  in  2\ 
grammes  of  flour.  This  multiplied  by  40  gives  the 
percentage.  From  this  total  percentage  deduct  the 
percentage  of  sugar  and  dextrin  found,  the  balance 
is  the  percentage  of  soluble  albuminoids. 

(5)  Starch. — After  determining  the  percentage 
of  moisture,  ash,  dry  gluten,  soluble  albuminoids, 
etc.,  the  amount  of  starch  in  flour  may  be  calculated 
roughly  by  difference.  Where  a  direct  determination 
is  required,  the  following  process,  described  in  Allen's 
commercial  organic  analysis,  will  be  found  useful. 

Any  fat  or  oil  should  first  be  removed  by  treat- 
ment with  ether.  The  flour  is  then  treated  with  a 
saturated  solution  of  salicylic  acid  in  cold  water. 
This  will  dissolve  alkaline  salts,  sugar,  dextrin,  etc. 
The  liquid  is  filtered  and  the  residue  washed  with 
decinormal  caustic  soda  to  remove  salicylic  acid  and 
albuminoids.  The  residue  is  rinsed  off  the  filter  with 
warm  water  and  heated  to  boiling  point,  in  order  to 
gelatinise  the  starch.  The  mixtures  must  be  kept 
constantly  stirred.  The  product  is  then  treated  with 
a  known  measure  of  recently  prepared,  and  filtered 
cold  infusion  of  malt,  of  which  the  specific  gravity 
has  been  previously  ascertained.    The  mixture  is 


Determination  of  Starch  in  Flour. 


67 


kept  at  a  temperature  of  about  140°  to  145  Fah., 
with  occasional  stirring,  until  a  drop,  taken  out  with  a 
glass  rod  and  added  to  a  drop  of  iodine  solution  on  a 
porcelain  plate,  shows  no  blue  or  brown  colouration. 
The  solution  is  then  filtered,  made  up  to  a  definite 
volume,  and  its  specific  gravity  accurately  ascertained. 
From  the  excess  of  the  density  over  water  is  sub- 
tracted the  density  due  to  the  infusion  of  malt  used, 
allowance  being  made  for  the  increased  volume  of  the 
liquid,  when  the  difference  represents  the  density  due 
to  the  starch  dissolved,  and  this  number  divided  by 
4*096  (  =  3*395  +  1*037)  gives  the  number  of 
grammes  of  starch  in  each  100  ex.  of  the  solution. 

Thus,  suppose  10  grammes  of  the  sample  be 
taken,  and,  after  treatment  with  ether  and  salicylic 
acid,  and  soda  solutions,  in  the  manner  described, 
the  residue  is  treated  with  50  c.c.  of  water  and  5  c.c. 
of  infusion  of  malt  of  1  *o6o  sp.  gravity;  the  liquid 
being  subsequently  made  up  to  100  c.c.  and  found  to 
have  a  density  of  1*033.     Then,  the  correction  due 

to  the  malt  infusion  will  be 

(1,060—1,000)  x  5_ 

1^0  3*' 

this  subtracted  from  the  difference  between  the  density 
of  the  solution  and  that  of  water  (1033  — 1000)  =  33 
leaves  30  as  the  excess  density  caused  by  the  solution 
of  the  starch  of  the  sample ;  and  this  figure,  divided  by 
4*096,  gives  7*324  grammes  per  100  c.c,  or  in  the  10 
grammes  taken  ;  or  73*24  per  cent,  of  starch  in  the 
sample. 


68        The  Chemistry  and  Practice  of  Sizing. 


The  following  simple  method  of  estimating  the 
amount  of  starch  in  flour  is  described  by  J.  Muter. 
The  author  has  found  it  very  serviceable.  "  It 
depends  upon  the  fact  that  starch  forms  an  insoluble 
compound  with  barium.  If  an  excess  of  baryta 
water  of  known  strength  be  added  to  starch  which 
has  been  previously  gelatinsed  in  water,  a  portion 
of  the  barium  will  combine  with  the  starch,  and  then 
by  estimating  the  amount  of  baryta  water  left  uncom- 
bined,  the  amount  taken  up  by  the  starch  may  be 
ascertained.  The  formula  of  the  starch-baryta  com- 
pound is  C24H4rJ02oBaO,  and  it  therefore  contains 
1 9' i  per  cent  of  BaO. 

The  Materials  required  are  ; — 

(1)  Decinormal  hydrochloric  acid,  containing 
3*65  grammes  of  real  HC1  per  1,000  c.c.  =  '00765 
BaO  for  each  c.c. 

(2)  Baryta  water  kept  in  a  special  jar  with  a 
burette  permanently  attached  as  shown  in  the  illustra- 
tion. (A)  is  the  jar  for  the  baryta  water,  having  a 
tube  attached  containing  lumps  of  quicklime  to 
prevent  the  entrance  of  C02  from  the  atmosphere 
when  any  liquid  is  run  off.  The  burette  (B)  is 
attached  to  the  bottom  neck  of  the  jar  by  a  tube 
having  a  pinchcock  (a)  to  admit  the  reagent,  and  a 
tube  (n)  filled  with  lumps  of  caustic  potash  to  prevent 
entrance  of  C02. 

(3)  Alcoholic  solution  of  phenol-phthalein  as  the 
indicator. 


Determination  of  Starch  in  Flour.  69 


The  Process. — 3  grammes  of  flour  are  first 
treated  with  ether  or  petroleum  spirit  in  the  "  Soxhlet" 
(see  chapter  on  cloth  analysis)  to  remove  any  fat. 
The  powder  is  then  well  rubbed  in  with  successive 
quantities  of  water  until  thoroughly  disintegrated,  the 
liquid  being  transferred  to  a  250  c.c.  flask,  100  c.c. 


Apparatus  for  the  estimation  of  Starch. 


of  water  in  all  being  used  to  entirely  transfer  the 
powder  from  the  mortar  to  the  flask.  The  flask  and 
contents  are  now  heated  on  the  water  bath  for  half- 
an-hour,  with  frequent  shaking,  to  entirely  gelatinise 
the  starch.    The  whole  is  then  cooled,  and  50  c.c.  of 


jo        The  Chemistry  and  Practice  of  Sizing. 


standard  baryta  water  having  been  added  from  the 
burette,  the  flask  is  corked,  well  shaken  for  two 
minutes,  proof  spirit  is  added  up  to  the  250  c.c. 
mark,  and  the  whole  again  shaken,  tightly  corked,  and 
set  aside  to  settle.  While  settling,  a  check  is  made 
on  10  c.c.  of  the  baryta  water  by  shaking  up  with 
100  c.c.  of  freshly  boiled  distilled  water,  in  a  250  c.c. 
corked  flask,  and  then  titrating  with  decinormal  HC1, 
in  the  presence  of  two  drops  of  phenol-phthalein 
solution.  The  number  of  c.c.  of  acid  used  is 
recorded,  giving  the  total  strength  of  50  c  c.  of  the 
baryta  water  employed.  When  the  main  analysis 
has  settled,  50  c.c.  of  the  clear  liquid  are  drawn  off 
with  a  pipette,  rapidly  titrated  with  the  decinormal 
acid  and  phenol-phthalein,  as  in  the  check,  and  the 
number  of  c.c.  of  acid  used  is  multiplied  by  5  and 
set  down  as  the  strength  of  baryta  water  remaining 
uncombined.  This  latter  amount  is  deducted  from 
the  total  check  strength,  and  the  difference  in  c.c.  of 
acid  is  multiplied  by  '00765,  which  gives  BaO  com- 
bined with  the  starch.  This  result  multiplied  by 
4*2353  gives  the  amount  of  starch  in  the  3  grammes 
taken  =  x  :  then 

— — - — !22  =  percentage  of  starch. 

The  determination  of  the  amount  of  starch  in 
a  sample  of  flour  may  also  be  made  in  the  following 
way  : — A  weighed  quantity  of  flour  is  kneaded  into 
a  dough  and  then  placed  on  a  fine  sieve  over  a  suitable 


Determination  of  Starch  in  Flour.  J  i 


vessel  for  collecting  the  starch.  A  stream  of 
water  is  allowed  to  trickle  over  it,  kneading  well  all 
the  time.  When  the  water  runs  away  clear  it  is 
allowed  to  stand,  and  when  the  starch  has  all  settled 
out,  the  water  is  poured  off  and  the  deposited  starch 
collected,  dried  at  iio°C,  and  weighed.  This 
method  is  convenient  but  rough." 

A  modification  of  the  above  test  may  be  made 
by  washing  the  starch  once  or  twice  with  water  and 
then  pouring  the  milky  liquid  into  a  long  graduated 
100  c.c.  measuring  glass,  and  allowing  the  starch  to 
settle  out,  In  every  case  the  mixture  of  starch  and 
water  should  stand  exactly  24  hours.  The  amount 
of  solid  starch  is  noted.  In  each  case  the  same 
weight  of  flour  should  be  used. 

The  following  table  will  give  some  idea  of  the 
proportions  of  the  various  ingredients  contained  in 
different  kinds  of  wheaten  flour. 


No,  1 
Wheaten 
Flour. 

No,  2 
Wheaten 
Flour. 

No.  3 
Wheaten 
Flour 

68-09 

70*05 

67-71 

9-88 

6-76 

2*36 

4*93 

517 

8'55 

3'Si 

4-11 

7*39 

Water  

1278 

I3'3I 

i3'52 

Mineral  Matter  

•81 

•60 

•47 

lOO'OO 

lOO'OO 

lOO'OO 

Moist  Gluten  

25-81 

good 

17-65 

good 

6-i8 
very  bad 

j  2        The  Chemistry  and  Practice  of  Sizing. 


Treatment  of  Flour  for  Sizing. 

When  the  starches,  such  as  farina  and  maize,  are 
examined  under  the  microscope,  it  will  be  seen  at 
once  that  the  granules  are  separate  and  distinct,  but 
when  wheaten  flour  is  examined  in  the  same  way,  it 
will  be  seen  that  the  starch  granules  are  held  together 
in  groups.  This  is  due  to  the  gluten  present  in  the 
flour,  and,  in  order  to  separate  the  granules,  it  is 
necessary  to  rub  the  flour  with  water  for  some  con- 
siderable time. 

In  the  same  way  it  is  essential,  before  using 
the  flour  for  making  into  size,  that  these  starch 
granules  shall  be  separated  from  each  other, 
because  it  has  been  found  by  experience  that 
the  best  results  are  obtained  when  the  groups  of 
starch  granules  are  entirely  broken  up,  so  that  each 
individual  granule  is  distinct  and  separate  from  its 
neighbour.  Yarn  sized  with  flour  in  this  condition 
is  much  smoother,  and  much  more  pliable,  than  if  the 
size  were  made  from  untreated  flour.  For  this 
reason  it  is  essential  that  flour  should  undergo  some 
preliminary  treatment  before  being  made  into  size. 

Many  very  different  opinions  are  expressed  by 
sizers  as  to  the  methods  to  adopt  in  the  treatment 
of  flour  in  order  to  get  the  best  results.  In  the 
past  it  was  customary  to  ferment  the  flour  for  long 
periods,  but  this  method  of  procedure  is  being 
rapidly  superseded,  except  for  certain  classes  of 
"light"  sizing,  by  the  more  economical  and  more 


Object  of  Fermenting  Flour.  73 


scientific  method  of  steeping  with  chlordide  of  zinc, 
whereby  fermentation  is  prevented. 

Object  of  Fermenting  Flour. 

The  process  of  fermentation  is  carried  on  by 
different  manufacturers  for  varying  lengths  of  time 
and  with  varying  objects.  Some  manufacturers 
ferment  their  flour  for  periods  ranging  from  one 
month  to  six  months.  Some  carry  out  the  process  in 
order  to  prevent  the  yarn  sized  with  it  having  a 
harsh  feel,  whilst  others  conduct  it  with  the  object 
}f  producing  antiseptic  substances,  in  order  to 
prevent  the  development  of  mildew  on  the  woven 
cloth. 

There  are  certain  manufacturers  who  possess  a 
high  reputation  for  China  shirtings  of  a  certain  class. 
The  warp  in  these  shirtings  is  sized  to  the  extent  of 
about  30  per  cent,  without  the  use  of  mineral  sub- 
stances like  China  clay,  and  without  the  use  of 
deliquescents  like  chloride  of  magnesium.  The  size 
consists  of  flour  and  tallow  only.  The  cloth  has  a 
characteristic  feel  and  appearance  when  woven,  and 
many  manufacturers  would  be  glad  to  know  the 
secret  possessed  by  those  who  are  engaged  in  man- 
ufacturing this  class  of  cloth.  The  main  secret  is  in 
the  treatment  of  the  flour  before  it  is  used.  It  is 
customary  to  ferment  the  flour  for  periods  ranging 
from  two  to  six  months.  The  effect  of  this  prolonged 
fermentation  is  to  produce  a  size  which  renders  the 


74        The  Chemistry  and  Practice  of  Sizing. 


yarn  pliable,  and  gives  a  full  mellow  feel  to  the 
woven  cloth. 

It  would  be  impossible  to  obtain  good  weaving- 
results  with  yarn  sized  to  the  extent  of  30  per  cent., 
with  flour  and  tallow  alone,  unless  the  flour  had 
been  previously  subjected  to  a  long  process  of  fer- 
mentation. The  reason  is,  of  course,  that  the  yarns 
would  be  so  harsh  and  brittle  that  good  weaving 
would  be  impossible. 

Why  flour  fermented  for  a  long  time  should  give 
a  much  softer  size  than  if  it  be  fermented  for  a  short 
time  only,  is  a  matter  requiring  explanation.  In 
the  first  place  it  is  due  to  the  breaking  up  of  the 
flour,  and  the  separation  of  the  starch  granules,  and 
in  the  second  place  it  is  due  to  the  decomposition 
of  the  gluten,  and  at  the  same  time  to  the  production 
of  greater  or  less  quantities  of  soluble  starch  and 
sugar.  This  soluble  starch  and  sugar  is  the  result 
of  bacterial  action,  and  in  its  production  the  original 
starch  loses  its  adhesive  properties  according  to  the 
amount  of  soluble  matter  formed. 

It  is  customary  for  manufacturers  who  size  the 
class  of  cloth  under  discussion  to  purchase  flour 
containing  as  high  a  percentage  of  gluten  as  possible. 
They  claim  that  from  such  a  flour  only  can  they  get 
the  right  percentage  of  size  on  the  warp  with  the 
desired  degree  of  softness. 

It  is  quite  true  that  a  flour  containing  a  high 
percentage  of  gluten  gives  the  results,  but  this  is 


Object  of  Fermenting  Flour.  7  5 


because  the  nitrogenous  gluten  is  an  excellent 
medium  for  bacterial  development,  and  the  more 
gluten  there  is  present  the  greater  is  the  production 
of  soluble  substances.  These  soluble  substances 
are  absorbed  by  the  yarn  when  the  latter  is  sized,  and 
although  the  flour  has  lost  some  of  its  adhesiveness 
and  a  great  deal  of  its  harshness  in  their  production,  it 
has  not  lost  the  power  of  adding  weight,  because  the 
soluble  matters  are  still  present. 

The  foregoing  is  the  true  explanation  of  the 
results  obtained  by  fermenting  a  highly  glutenous 
flour  for  long  periods,  but  in  the  opinion  of  the 
authors  these  results  could  be  obtained  equally  well, 
if  not  better,  by  using  a  flour  not  so  rich  in  gluten 
in  conjunction  with  a  soluble  starch  or  white  dextrin. 
If  the  flour  be  mixed  with  a  definite  amount  of  these 
substances  the  time  required  for  fermenting  could 
be  reduced  to  three  weeks  or  a  month.  This  would 
mean  that  a  considerable  reduction  could  be  made 
in  the  quantity  of  flour  laid  down  at  one  time,  and 
would  save  a  considerable  amount  of  beck  space.  It 
would  be  cheaper  to  add  soluble  starch  or  white 
dextrin  to  the  size,  thus  saving  the  enormous  loss  in 
material  which  takes  placeduring  a  long  fermentation, 
for  not  only  is  soluble  starch  produced  by  this  process, 
but  some  of  it  is  further  converted  into  alcohol,  and 
acetic  and  lactic  acids,  as  the  fermentation  is  con- 
tinued. The  production  of  these  latter  substances 
is  a  distinct  loss  to  the  manufacturer,  as  they  are 


J  6        The  Chemistry  and  Practice  of  Sizing. 


quite  useless  for  sizing  purposes.  How  much  loss 
is  entailed  cannot  be  calculated,  but  in  a  year's 
working  with  a  bio-  firm  it  must  be  enormous. 

If,  however,  the  flour  be  fermented  with  the  object 
of  producing  wheaten  starch  at  a  less  cost  than  it 
can  be  bought  from  the  dealers,  and  the  production 
of  wheaten  starch,  with  more  or  less  soluble  starch 
is  the  real  object  of  a  lengthy  fermentation,  whether 
the  sizer  knows  it  or  not,  then  it  must  be  self  evident 
that  the  most  suitable  flour  to  use  for  subjecting  to 
this  process  will  be  one  in  which  the  wheat  is  well 
matured,  and  one  which  must  therefore  be  rich  in 
starch.  The  percentage  of  gluten  may  be  fairly  low 
so  long  as  it  is  of  high  quality,  and,  as  a  matter  of 
feet,  it  is  impossible  to  get  a  condition  where  the 
gluten  is  of  high  quality  and  the  starches  of  a  poor 
quality. 

If  the  manufacturer  be  also  depending  upon 
the  antiseptic  matters,  he  must  boil  up  the  flour 
with  the  water  in  which  it  has  been  fermented,  but 
this  is  really  a  most  objectionable  method  of  prepar- 
ing size.  It  usually  has  a  most  abominable  smell 
which  is  imparted  to  the  woven  cloth,  and  makes 
the  atmosphere  of  the  weaving  shed  most  trying  to 
those  unaccustomed  to  it. 

There  is  no  doubt  also,  that  fermented  flour  is  not 
so  liable  to  develope  mildew  as  unfermented  flour. 
But  this  is  due,  in  the  first  place,  to  the  fact  that  the 
resultant  wheaten  starch,  freed  from  the  nitrogenous 


Object  of  Fermenting  Flour. 


gluten,  is  not,  in  itself,  so  suitable  a  medium  for 
mildew  growths  as  flour  in  its  natural  condition. 
In  the  second  place,  the  antiseptic  substances 
formed  by  the  decomposition  of  the  sugar  and 
dextrin  tend  to  prevent  the  setting  up  of  mildew. 
At  the  same  time  the  uncertain  amount  of  antiseptic 
matter  produced  never  pays  for  the  loss  of  material 
and  time,  and  if  the  production  of  antiseptics  were 
the  only  object  in  fermenting  flour,  the  whole  matter 
would  be  an  absurdity,  as  suitable  antiseptics  of 
known  and  definite  properties,  such  as  salicylic  acid 
and  carbolic  acid,  could  be  used  to  greater  advantage. 

Some  manufacturers  allow  the  starchv  matter  to 
settle,  and  run  off  the  water.  If  this  be  done  the  whole 
of  the  antiseptic  substances  are  lost.  As  a  matter 
of  fact  the  loss  of  the  antiseptic  substances  produced 
by  fermenting  flour  need  never  be  considered  at  all, 
and  where  it  is  customary  to  run  off  the  liquor  in 
which  the  flour  has  been  steeped,  it  is  only  necessary 
to  boil  the  starchy  matter  with  salicylic  acid,  in 
the  proportion  of  four  to  six  ounces  of  the  acid  to 
each  100  pounds  of  starch,  to  prevent  mildew,  and 
thus  avoid  the  use  of  evil-smelling  size. 

It  will  be  perfectly  evident  to  the  sizer  that  if  he 
is  o-oincr  to  ferment  in  order  to  manufacture  his  own 

o  o 

wheaten  starch,  it  will  be  more  economical  to  purchase 
flour  with  a  higher  percentage  of  starch  and  a  lower 
percentage  of  gluten,  so  long  as  the  gluten  is  of 
good  sound  quality. 


jS       The  Chemistry  and  Practice  of  Sizing. 

It  would  obviously  be  a  mistake  to  use  a  flour 
containing,  say,  15  per  cent,  of  dry  gluten  if  the 
manufacturer  can  get  equally  good  results  with  one 
containing  6  per  cent.  The  former  flour  would 
probably  cost  more  than  the  latter,  and  would 
be  more  wasteful,  because  the  amount  of  starch 
would  be  greater  in  the  cheaper  flour  than  in  the 
dearer  one.  At  the  same  time,  the  manufacturer 
must  remember  that  a  cheap  flour,  containing 
gluten  of  poor  quality,  is  not  suitable  for 
fermentation.  The  starch  is  never  of  good 
quality,  and  very  often  putrefactive  fermentation 
sets  up,  making  the  size  very  objectionable  in 
smell,  and  liable  to  develop  mildew  on  the  cloth 
afterwards. 

The  authors  often  wonder  to  what  extent  this 
objectionable  smell  of  putrid  size  has  influenced  the 
authorities  in  the  matter  of  the  ventilating  of 
weaving  sheds.  The  irony  of  the  position  will  be 
appreciated  when  it  is  realised  that,  as  a  rule,  these 
weaving  sheds  do  not  come  within  the  Act  relating 
to  ventilation,  because  they  do  not  use  artificial 
humidity  for  assisting  the  weaving. 

Where  the  process  of  fermentation  is  carried  out, 
the  manufacturer  should  insist  upon  the  becks  being 
thoroughly  cleaned  out  with  boiling  water  and 
washing  soda,  before  a  fresh  lot  of  flour  is  laid  down. 
The  becks  should  afterwards  be  kept  carefully 
covered  over  in  order  to  prevent,  as  far  as  possible, 


Acids  in  Fermented  Flour.  79 


the  spores  of  mildew  getting  into  the  flour  at  this 
stage.  By  careful  attention  to  these  details,  after- 
troubles  may  be  avoided. 

All  fermented  flour  contains  varying  quantities 
of  acids,  In  some  cases  the  authors  have  actually 
found  the  amount  to  be  over  one  per  cent, 
of  the  total  mixture  of  flour  and  water.  The  presence 
of  acids  may  be  shown  by  dipping  a  piece  of  blue 
litmus  paper  into  the  mixture.  If  acids  be  present 
the  litmus  paper  becomes  red.  These  acids,  which 
consist  principally  of  acetic  acid  and  lactic  acid, 
should  always  be  carefully  neutralised  with  caustic 
soda.  This  is  important  for  several  reasons.  In 
the  first  place  acids  have  a  strong  tendency  to 
cause  the  reeds  in  the  looms  to  rust,  thus  producing 
iron  stains  on  the  cloth.  Acid  size  will  also  act 
chemically  upon  the  copper  rollers  in  the  tape  frame, 
and  the  copper  boil  pipes  in  the  sow  box  and  in  the 
becks.  The  copper  is  more  or  less  quickly  dissolved, 
and  the  copper  solution  tints  the  size  green.  This 
action  may  take  place  on  some  copper  rollers  and 
pipes,  and  might  not  have  any  action  on  others.  A 
great  deal  depends  upon  the  natureof  the  copper  from 
which  they  have  been  made.  Some  copper  rollers 
tarnish  much  more  readily  than  others.  This  is  due 
to  the  nature  of  the  copper.  The  action  of  acid  size 
is  very  noticeable  on  copper  which  is  liable  to 
tarnish.  The  acids  readily  attack  the  tarnished 
places,  dissolving  the  tarnish,  and  the  freshly  exposed 


8o        The  Chemistry  and  Practice  of  Sizing. 


surface  readily  tarnishes  again  when  the  tape  frame 
is  stopped.  These  fresh  places  are  again  acted 
upon  by  the  acids,  and  if  this  is  not  attended  to  the 
roller  will  soon  become  worn  out  and  useless.  The 
writer  has  been  frequently  called  in  by  manufacturers 
where  this  trouble  has  occurred,  and  in  all  cases  it 
has  been  found  that  the  size  gave  an  acid  reaction, 
due  either  to  the  flour,  or  to  the  presence  of  rancid 
or  impure  tallow  in  the  mixing. 

It  is  of  interest  to  note  that  damage  through  the 
action  of  these  acids  may  generally  be  minimised  if 
each  copper  roller  be  carefully  polished  before 
being  used,  care  being  taken  to  remove  every 
trace  of  tarnish  from  it.  The  following  instance 
which  came  under  the  writers  notice  some  time 
ago,  is  a  good  illustration  of  this  fact.  The  trouble 
had  been  going  on  for  about  ten  days,  and  was 
causing  considerable  inconvenience.  It  was  not  con- 
venient  to  neutralise  the  size  (which  was  found  to 
be  acid)  at  the  time  of  the  visit  to  the  mill,  and  so 
the  roller  was  taken  out  for  examination.  On  care- 
ful inspection  it  was  seen  that  the  corrosion  was 
taking  place  in  certain  places  only.  A  new  roller 
was  obtained,  and  the  writer  saw  that  it  was 
thoroughly  scoured  and  polished  to  remove  every 
trace  of  tarnish.  The  old  size  in  the  sow  box  was 
cleaned  out,  and  the  roller  put  into  position.  The 
size  was  pumped  in,  and  the  operation  of  sizing  the 
yarn  was  continued  without  any  further  objectionable 


Acids  in  Fermented  Flour, 


81 


results.  The  old  roller  was  then  thoroughly  scoured 
and  polished,  and  afterwards  used  without  the 
production  of  the  green  colour  in  the  size. 

An  interesting  case  of  damage,  traceable  to  acid 
size,  came  under  the  authors'  notice  some  months 
ago.  A  certain  firm  had  been  caused  considerable 
loss  and  annoyance  through  the  healds  wearing  out 
long  before  good  healds  should  be  affected  at  all. 
It  was  not  a  case  of  using  inferior  healds,  nor  was 
it  confined  to  the  healds  of  any  particular  maker. 
This  trouble  had  been  going  on  for  a  long  time, 
until  the  manager  commenced  using  caustic  soda  for 
the  purpose  of  neutralising  the  acids  of  the  fermented 
flour.  This  experiment  was  carried  out  without  any 
expectation  of  its  affecting  the  healds,  but  a  change 
in  the  wearing  of  the  latter  was  seen  as  soon  as 
the  first  lot  of  beams  were  sent  into  the  weaving 
shed,  and,  without  making  any  other  change,  the 
damage  was  stopped.  It  is  quite  probable  that  very 
acid  size  will  affect  the  varnish  of  the  healds,  and 
thus  cause  a  large  amount  of  breakages. 

Caustic  soda  may  be  used  for  the  purpose  of 
neutralising  acid  in  flour  size.  It  is  of  the  utmost  im- 
portance that  the  caustic  soda  should  be  diluted  with 
water  as  much  as  possible,  otherwise  it  will  coagulate 
the  flour.  The  lumps  thus  formed  are  very  difficult 
to  remove,  even  on  prolonged  boiling.  The  diluted 
solution  must  be  added  in  a  thin  stream  to  the  size, 
which  should  be  kept  constantly  agitated  during  the 

F 


82         The  Chemistry  and  Practice  of  Sizing, 

operation  by  means  of  the  dashers.  When  the 
acidity  has  been  destroyed  the  blue  litmus  paper 
ceases  to  turn  red  on  being  dipped  into  the  size. 

If  sizers  had  some  knowledge  of  volumetric 
analysis  it  would  be  possible,  in  a  few  minutes,  to 
ascertain  the  exact  amount  of  caustic  soda  which 
would  be  required  to  neutralise  the  acidity  of  the  size, 
and  thus  save  continual  testings  with  litmus  paper. 

The  following  method  of  procedure,  although 
rough  and  ready,  might  be  adopted  in  order  to 
avoid  the  waste  of  time  which  would  take  place 
if  the  caustic  soda  be  added  without  any  idea  of  the 
amount  required  : — 10  grammes  of  the  size  should 
be  carefully  weighed  in  a  beaker.  A  few  drops  of 
phenol-phthalein  is  then  added,  and  the  mixture 
titrated  with  a  normal  solution  of  caustic  soda, 
from  a  burette,  until  the  last  drop  turns  the  size  pink. 

One  c.c.  of  the  solution  of  caustic  soda  contains 
0*04  gramme  of  real  caustic  soda,  and  this  number, 
multiplied  by  the  number  of  c.c.  used,  and  afterwards 
by  10,  will  give  the  percentage  of  caustic  soda 
required  to  neutralise  the  size.  This  may  be 
reckoned  either  in  grammes  or  pounds  to  suit  the 
convenience  of  the  experimenter. 

Steeping  with  Chloride  of  Zinc. 

The  authors  have  already  stated  that  the  main 
object  of  fermenting  flour,  or  of  steeping  it  with 


Steeping  zuith  Chloride  of  Zinc.  83 


chloride  of  zinc,  is  to  separate  the  starch  granules 
from  the  gluten.  This  result  may  be  obtained 
equally  well  by  either  process,  but  where  there  is  no 
objection  to  the  use  of  chloride  of  zinc  in  the  size, 
there  is  everything  to  gain  and  nothing  to  lose  by 
steeping  with  zinc. 

The  following  are  some  of  the  principal  advan- 
tages obtained  by  subjecting  flour  to  the  steeping 
process  : — 

(1)  The  gluten  of  the  flour  is  retained,  and  its 
powerfully  adhesive  properties  can  be  employed  in 
assisting  in  fixing  the  China  clay  to  the  yarn. 

(2)  There  is  no  loss  in  the  starch,  as  is  the  case 
when  the  flour  is  fermented,  and  consequently  the 
whole  of  the  adhesive  powers  of  the  starch  are 
retained  for  strengthening  the  yarn,  and  fixing  the 
China  clay, 

(3)  The  size  does  not  develope  acids,  and  there 
is  an  entire  absence  of  the  disagreeable  smell 
which  is  almost  always  present  in  fermented  flour. 
Putrefactive  decomposition  is  impossible  in  the 
steeping  process,  no  matter  how  long  the  chloride 
of  zinc  and  flour  are  left  together. 

(4)  There  is  no  risk  of  loss  in  the  steeping 
process  through  the  contents  of  the  beck  over- 
flowing, as  is  very  often  the  case  where  the  flour  is 
fermented,  especially  in  hot  weather. 

(5)  There  is  less  chance  of  the  chloride  of  zinc 
being  omitted  from  any  single  mixing  where  the 


84        The  Chemistry  and  Practice  of  Sizing, 


steeping  process  is  carried  out,  than  is  the  case 
where  the  chloride  of  zinc  is  added  to  every  mixing 
separately.  This  is  a  consideration  of  the  utmost 
importance,  as  many  cases  of  mildew  come  under 
the  authors'  notice  which  are  entirely  due  to  the 
chloride  of  zinc  having  been  left  out  of  a  mixing 
through  a  lapse  of  memory  on  the  part  of  the  size 
mixer. 

(6)  Where  the  steeping  process  is  carried  out,  the 
flour,  which  is  the  substance  most  liable  to  mildew,  is 
brought  into  direct  and  intimate  contact  with  the 
substance  which  is  used  for  the  purpose  of  preventing 
mildew.  A  further  consideration  is,  that  the  chloride 
of  zinc  becomes  intimately  mixed  with  the  starch 
granules  before  its  antiseptic  action  is  diluted  through 
the  addition  of  the  other  ingredients  of  the  size. 

(7)  Chloride  of  zinc  has  the  power  of  acting  upon 
the  gluten  of  the  flour,  and  the  cellulose  of  the 
starch,  in  a  similiar  manner  to  mineral  acids,  and  in 
consequence  the  starch  granules  are  quickly  separ- 
ated, thus  bringing  the  flour  into  the  condition  in 
which  it  is  suitable  for  use  in  a  very  short  time. 

(8)  Less  beck  space  is  required  when  the  flour 
is  steeped  with  chloride  of  zinc  because  more  flour 
can  be  put  down  at  one  time  in  a  beck  of  a  given 
capacity,  as  there  is  no  danger  of  overflowing. 

(9)  Greater  uniformity  in  the  strength  of  the 
size  can  be  maintained  when  the  flour  is  steeped 
with  zinc.    As  there  is  no  chemical  change,  and  no 


Use  of  Wheat  en  Flour  in  Sizing. 


loss  through  the  production  of  sugar,  alcohol  and 
acids,  the  flour  remains  at  a  constant  standard  of 
strength.  Therefore,  instead  of  depending  upon  the 
strength,  as  tested  by  the  number  of  degrees  the 
mixture  of  flour  and  water  may  Twaddell,  the  size 
mixer  simply  runs  off  so  many  inchesof  the  mixture  to 
the  weight  of  dry  flour  he  may  require  for  a  mixing. 

Where  the  steeping  process  is  carried  out  the 
flour  should  remain  in  contact  with  the  water  and 
the  chloride  of  zinc  for  about  a  fortnight.  In  this 
time  it  is  rendered  fit  for  use.  The  quantity  of 
chloride  of  zinc  which  should  be  used  per  pack  of 
flour  (280  lbs.),  is  from  3^  to  4  gallons,  at  ioo°  to 
102°  Tw.  This  matter  is  further  discussed  under 
chloride  of  zinc,  and  also  in  the  chapters  on  size 
mixing  and  mildew. 

Use  of  Wheaten  Flour  in  Sizing. 

Wheaten  flour  is  undoubtedly  the  best  adhesive 
substance  to  use  for  all-round  work  in  sizing,  and 
where  weaving  is  the  first  consideration,  it  cannot  be 
improved  upon.  There  are,  however,  certain  cloths 
in  which  a  particular  "feel"  and  appearance  is 
required,  and  these  conditions  can  be  better  obtained 
by  the  addition  of  one  or  other  of  the  various 
starches.  This  is  a  matter  which  will  be  more 
fully  dealt  with  when  these  starches  are  discussed. 

It  is  often  suggested  that  flour  might  be  abolished 
altogether  from  sizing,  and  a  pure  starch  such  as  farina 


86        The  Chemistry  and  Practice  of  Sizing. 


substituted,  because  this  substance  does  not  develope 
mildew  to  the  same  extent  as  a  nitrogenous  body 
like  wheaten  flour.  In  the  authors'  opinion  there 
is  nothing  better  than  flour  for  medium  and  heavy 
sizing.  With  regard  to  mildew,  this  is  not  a  matter 
worth  considering  at  all,  as  mildew  can  always  be 
avoided  by  the  proper  use  of  antiseptics, 

It  is  a  constant  source  of  complaint  that  a  size 
mixing,  supposed  to  produce  a  certain  weight  and 
feel,  does  not  give  the  same  results  in  the  hands  of 
one  manufacturer  as  it  does  in  the  hands  of  another,- 
even  where  exactly  the  same  method  of  procedure 
is  adopted  in  mixing. 

If  the  same  weights  and  qualities  of  the  various 
ingredients  are  used,  and  if  exactly  the  same  treat- 
ment is  accorded,  it  is  impossible  to  get  different 
results.  The  explanation  as  to  why  differences 
occur  is  that  two  firms  rarely  use  the  same 
"standards"  in  their  materials.  The  two  substances 
which  most  affect  the  character  of  the  size  are  the 
flour  and  the  China  clay. 

The  writer  has  always  had  to  contend  with  this 
difficulty  in  laying  down  mixings,  and,  unless  the 
strength  and  character  of  the  flour  and  the  nature 
of  the  clay  be  known,  a  mixing  is  bound  to  vary  in 
different  hands.  This  is  the  reason  why  size  mixings 
given  in  books  should  be  taken  as  a  working  basis 
only.  If  flour  of  a  regular  strength  and  China  clay 
of  a  regular  quality  could  always  be  obtained  it 


Farina  or  Potato  Starch. 


87 


would  not  be  a  difficult  matter  to  keep  size  mixings 
uniform.  A  miller,  who  knows  his  business  as  far 
as  sizing  flours  is  concerned,  may,  by  the  judicious 
mixing  of  various  classes  of  flours,  always  be  in  a 
position  to  supply  a  flour  which  is  constant  in 
strength.  In  technical  language  he  will  "standardise" 
his  flour. 

The  importance  of  conditions  such  as  these 
cannot  be  over-rated,  and,  until  manufacturers  realise 
this  fact,  there  will  always  be  a  want  of  uniformity  in 
the  results  obtained,  however  much  care  may  be 
exercised  in  making  the  size.  This  is  the  explanation 
why  a  certain  mixing  may  be  successful  at  one  mill 
and  may  not  work  wTell  in  another. 


FARINA  OR  POTATO  STARCH. 

Farina  is  obtained  from  the  tuber  of  the  potato 
plant  (solatium  tuberosum).  The  potato  consists 
principally  of  starch  and  water,  fully  75  per  cent,  of 
the  latter  substance  being  present  in  the  average 
sample.  Under  careful  cultivation  the  potato  may 
be  got  to  yield  about  20  per  cent,  of  starch. 

Farina  has  a  peculiar  glistening  appearance 
and  is  much  crisper  to  the  touch  than  any  of  the 
other  starches.  This  crispness  depends,  to  a  great 
extent,  upon  the  amount  of  moisture  present  in  the 
sample,  the  crispness  decreasing  as  the  moisture 


88       The  Chemistry  and  Practice  of  Sizing. 


increases.  Farina  forms  a  semi-transparent  paste 
when  boiled  with  water,  and  by  this  characteristic 
appearance  it  may  be  distinguised  from  the  other 
starches  used  in  sizing.  Weight  for  weight  it 
produces  a  thicker  paste  than  any  other  starch 
except  maize. 

The  following  analysis  shows  the  average  com- 
position of  the  potato  under  careful  cultivation  : — 


Per  cent. 

Starch        ..         ...  ...  ...  20*00 

Fat  or  Oil   ...        ...  ...  ...  o'io 

Cellulose     ...       ...  ...  ...  1  55 

Gum  or  Sugar       ...  ...  ...  1*05 

Nitrogenous  Substances  ...  2*27 

Ash  ...        ...        ...  ...  ...  1*02 

Water         ...        ...  ...  ...  74*oi 


IOO'OO 


Although  the  potato  contains  so  much  less  starch 
than  wheat  the  product  of  starch  per  acre  is 
greatly  in  favour  of  the  former. 

Manufacture  of  Farina. — Few  operations  are 
more  simple  than  the  extraction  of  starch  from 
potatoes,  nothing  further  being  necessary  than  the 
rupturing  of  the  cellular  tissue  by  rasping  or  grating, 
thus  liberating  the  starch  granules.  The  pulp 
obtained  is  washed  upon  a  metallic  plate  or  stage, 
by  means  of  a  stream  of  wTater,  and  the  washings 
passed  through  a  sieve.  The  solid  matter  of  the 
potato  is  left  on  the  plate,  whilst  the  sieve  separates 


Manufacture  of  Farina. 


89 


the  other  impurities.  This  sieve  allows  the  starch 
to  pass  through,  which  is  carried  forward  by  means 
of  the  water.  The  starch  is  further  purified  by 
washing  and  decantation.  The  operations  involved 
in  the  process  are  further  detailed  as  follows  : — 

Steeping  the  Potatoes. — This  is  done  previous 
to  washing,  for  the  purpose  of  softening  the  earth 
and  clay  adhering,  and  so  rendering  the  washing 
process  more  easy.  The  potatoes  are  steeped  in  a 
large  trough  from  six  to  twelve  hours,  according  to 
the  amount  of  impurities. 

Washing. — This  operation  is  effected  by  mechan- 
ical means,  and  by  the  aid  of  steam. 

Rasping  or  Grating. — The  object  of  rasping- 
is  to  reduce  the  potatoes  to  a  pulp,  so  rupturing  the 
cell  walls  containing  the  starch  granules. 

The  more  thoroughly  this  rasping  is  effected, 
the  easier  it  becomes  for  the  starch  to  escape.  As 
a  general  rule  the  washing  and  rasping  processes  are 
conducted  in  a  machine  which  allows  the  operations 
to  proceed  consecutively.  The  starch,  having  been 
washed  by  means  of  a  stream  of  water,  is  purified 
by  first  allowing  the  liquid  to  settle  for  a  few  hours. 
The  supernatent  liquid  is  removed  by  syphoning, 
and  the  starch  residue  is  mixed  with  its  own  bulk  of 
water,  and  passed  through  a  series  of  fine  sieves  to 
remove  stones,  sand,  and  other  impurities.  It  is 
again  allowed  to  settle,  the  liquid  syphoned  off,  and 
the  solid  starch  re-agitated  with  fresh  water,  and 


90       The  Chemistry  and  Practice  of  Sizing. 


either  passed  through  a  very  fine  brass  wire  sieve, 
or  filtered  through  silk.  The  liquor  is  again  allowed 
to  separate  from  the  starch  and  it  is  then  removed, 
leaving  the  starch  ready  for  drying. 

Drying. — This  operation  is  a  very  necessary 
one,  as  starch  retains  a  large  amount  of  moisture. 
The  starch  is  first  placed  in  the  form  of  solid 
blocks  on  beds  of  plaster  of  Paris,  which  absorb 
a  large  amount  of  the  water.  The  blocks  of 
starch  are  further  dried  in  heated  chambers,  through 
which  a  current  of  fresh  air  is  being  constantly 
passed.  The  temperature  of  these  chambers  should 
never  exceed  2  1  2  degrees  Fah. 

Germany  and  Holland  are  the  principal  countries 
in  which  the  potato  is  cultivated  for  the  extraction 
of  starch.  In  Germany  particularly,  the  cultivation 
has  been  carried  out  to  a  high  state  of  perfection, 
and  German  farinas  are  superior  to  any  other.  So 
greatly  does  a  good  farina  differ  from  a  poor  one, 
that  it  is  possible  for  the  expert  to  determine,  by  the 
microscopical  appearance  of  the  starch  granules, 
whether  the  starch  be  Dutch  or  German.  In  the 
latter  case  the  granules  are  composed  of  evenly- 
formed  medium-sized  corpuscles,  whilst  in  the  former 
they  are  very  irregular  in  size,  being  composed  of 
large  and  small  corpuscles.  Farina  consisting  of 
regular-sized  granules  is  invariably  the  best  for  sizing 
purposes.  It  produces  the  thickest  paste  on  boiling 
with  water,  and  the  paste  is  not  so  liable  to  liquefy 


Dutch  and  German  Farina.  gi 


as  that  formed  by  farina  composed  of  irregular-sized 
granules.  This  is  a  matter  of  vital  importance  in 
sizing-  as  it  would  mean  that  if  an  inferior  grade  of 
farina  should  be  used  the  yarns  sized  with  it  would 
very  quickly  become  "soft,"  giving  rise  to  the  state 
known  as  "soft  beams."  This  would  be  more 
especially  the  case  where  the  beams  had  to  remain 
in  the  weaving  shed  for  a  lengthy  period. 

The  reason  why  Dutch  farina  is  more  liable  to 
produce  "soft  beams"  than  German  farina  is  because 
it  is  more  susceptible  to  bacterial  action.  This  may  be 
accounted  for  in  several  ways,  In  the  first  place  the 
question  of  cultivation  must  be  taken  into  account, 
and  in  the  second  place  the  nature  of  the  soil,  and 
the  nature  of  the  water  used  in  the  preparation  of  the 
farina,  must  be  considered.  It  is  highly  probable 
that  the  starch  developed  in  a  potato  in  a  damp  soil 
like  that  which  characterises  Holland  secretes 
nitrogenous  matter  in  the  granule.  This  will  render 
it  more  susceptible  to  bacterial  action.  That  the 
water  used  in  the  preparation  of  the  farina  may 
account  for  this  liability  to  bactefial  attack  is  already 
recognised,  as  some  of  the  Dutch  firms  are  now 
using  distilled  water  instead  of  ordinary  water.  The 
authors  have  previously  mentioned  that  the  starches 
most  liable  to  liquefy,  after  -being  made  into  pastes 
with  boiling  water,  are  those  which  are  developed 
underground,  and  that  this  characteristic  is  not  shown 
to  the  same  extent  in  those  developed  above  ground 


92        The  Chemistry  and  Practice  of  Sizing. 


such  as  the  starch  from  seeds,  and  the  pith  of  plants- 
This  goes  to  support  the  authors'  contention  that  the 
character  of  the  soil  in  which  the  potato  has  grown 
plays  a  most  important  part  in  the  question  of  the 
liability  of  any  particular  sample  of  farina  paste  to 
bacterial  action. 

Size  made  from  farina  will  not  stand  prolonged 
boiling.  Under  this  treatment  it  quickly  loses  its 
adhesiveness.  Unfortunately  it  is  impossible  to 
ascertain,  by  any  simple  test,  the  amount  of  loss  of 
strength,  and  consequently  size  left  overnight  is 
either  thrown  away  or  more  farina  must  be  added 
to  approximately  make  up  the  loss.  Whatever  is 
done  leaves  the  sizer  in  a  most  unsatisfactory 
position.  If  he  throws  away  the  old  size  he  is  suffer- 
ing daily  loss,  and  if  he  adds  more  farina  he  is  put 
to  an  expense  which  ought  not  to  occur,  and  the 
size  is  uncertain  in  strength. 

This  objectionable  feature  has  been  overcome  to 
a  great  extent  by  treating  farina  size  with  caustic 
soda.  By  experiments  in  the  laboratory  it  was  found 
that  farina  treated  with  this  alkali  would  keep  its 
adhesiveness  for  a  great  length  of  time. 

The  following  description  gives  the  details  of  the 
experiments: — Seven  grammes  of  the  farina  were 
carefully  weighed,  and  mixed  with  200  cubic 
centimeters  of  water  in  dn  evaporating  basin. 
The  mixture  was  boiled  for  half-an-hour  on  the  water 
bath  described  on  pages  55  and  56,  and  set  aside  to 


Use  of  Caustic  Soda  with  Farina.  93 


cool  Another  portion  from  the  same  farina  was 
treated  in  a  similar  manner,  but  with  the  addition  of 
one  per  cent,  of  caustic  soda.  The  following  day  the 
two  samples  were  boiled  up  again.  The  first  showed 
signs  of  liquefaction,  but  the  second  showed  no 
change.  The  boiling  was  continued  day  by  day 
for  a  week,  an  equal  quantity  of  water  being  added 
in  each  case  to  make  up  for  loss  by  evaporation. 
The  samples  were  then  allowed  to  stand.  At  the 
end  of  three  more  days  the  sample  which  had  not 
been  treated  with  caustic  soda  was  liquid,  and 
covered  with  yellow  and  purple  mildew,  whilst  that 
containing  caustic  soda  was  firmer  than  was  the 
sample  of  paste  boiled  without  the  caustic  soda 
originally,  and,  although  they  had  stood  exposed 
side  by  side,  the  former  sample  did  not  show  the 
slightest  trace  of  mildew  after  being  exposed  for  a 
further  period  of  six  weeks. 

The  manufacturer  will  see,  therefore,  that  not 
only  does  caustic  soda  preserve  the  strength  of  farina 
size,  but,  by  its  action  in  preventing  the  decom- 
position of  the  starch  through  bacterial  action,  and 
thus  preventing  the  formation  of  acids  which  would 
otherwise  be  left  as  free  acids,  it  acts  as  an  antiseptic, 
preventing  the  development  of  mildew. 

Since  making  these  laboratory  experiments,  the 
writer  has  supervised  the  treatment  of  farina  size  in 
many  mills  with  the  same  success.  Caustic  soda 
has  the  further  advantage  of  not  being  injurious  in 


94         The  Chemistry  and  Practice  of  Sizing, 

any  way  to  cotton.  It  does  not  affect  it  disadvan- 
tageously  for  bleaching,  rather  the  reverse.  At  the 
same  time  it  must  be  used  judiciously,  otherwise  a 
little  trouble  will  ensue.  The  first  use  of  the  caustic 
soda  should  be  made  under  expert  supervision,  and 
afterwards  no  fear  of  trouble  need  be  felt. 

If  the  above  treatment  be  carried  out,  larger 
quantities  of  farina  may  be  laid  down  at  one  time, 
and  the  size  kept  much  more  uniform.  The  loss  of 
strength  in  the  mixture  will  be  prevented,  making  a 
very  considerable  saving  at  the  end  of  a  year. 

In  the  summer  it  is  necessary  to  add  a  greater 
percentage  of  caustic  soda,  especially  where  the  size 
is  standing  over  the  week-end,  say  from  Friday  to 
Monday.  This  is  more  particularly  the  case  during 
close  and  thundery  weather.  Under  such  conditions 
acid  is  developed  rapidly,  just  as  beer  and  milk  are 
soured,  and  unless  an  extra  quantity  of  alkali  be 
added,  the  acid  may  be  sufficient  to  entirely 
neutralise  the  caustic  soda  present,  and  by  Monday 
a  sour  size,  with  a  loss  of  strength  on  boiling  up, 
will  be  the  result.  The  alkali  requires  using  in  an 
intelligent  manner  to  get  the  best  results. 

Since  the  first  edition  of  this  book  was  issued 
nine  years  ago,  caustic  soda  has  come  into  general 
use  for  sizing  purposes.  The  authors  claim  to  be 
the  first  to  point  out  the  special  advantages  of  this 
substance  in  preventing  ''soft  beams"  when  used 
with  farina.     It  is  therefore,  somewhat  amusing  to 


Determination  of  the  Value  of  Farina.  95 

find  the  matter  being  periodically  re-discovered,  and 
either  offered  free  to  the  world  at  large,  from  motives: 
more  or  less  philanthropic,  or  sold,  in  the  form  of 
some  secret  and  mysterious  preparation,  generally 
as  a  liquid,  or  in  the  form  of  a  watery  soap  contain- 
ing a  certain  amount  of  free  alkali,  at  a  price 
considerably  in  excess  of  the  value  of  the  active 
ingredient. 

Determination  of  the  Value  of  Farina. 

Colour. — Farina  intended  for  sizing  purposes 
should  be  of  good  colour.  Dark  samples  will  impart 
their  shade  to  the  cloth,  and  where  whiteness  is 
required,  such  a  sample  would  be  very  objectionable. 

Moisture. — Farina  contains  a  larger  amount  of 
water  than  any  of  the  other  starches.  This  varies 
from  17  to  20  per  cent.  It  is  always  advisable  to 
estimate  the  quantity  of  moisture  present,  following 
the  method  of  procedure  given  on  page  23.  Every- 
thing else  being  equal,  the  farina  having  the  least 
percentage  of  water  should  be  chosen. 

Strength  of  Farina  Pastes. — A  suitable  test 
for  the  quality  of  a  sample  of  farina  is  made  by 
comparing  the  strength  of  the  paste,  formed  on  boil- 
ing it  with  water,  with  a  standard  sample  of  good 
quality.  The  process  has  been  given  under  flour  on 
pages  55  and  56,  but  in  the  case  of  farina,  seven 
grammes  of  the  starch  should  be  used  to  100  cubic 
centimeters  of  water.     If  the  proportions  given  under 


g6        The  Chemistry  and  Practice  of  Sizing. 


flour  were  used,  a  paste  is  formed  which  is  too  thick 
to  determine  the  quality  or  difference  in  stiffness  to 
a  nicety. 

It  is  necessary  to  carry  out  this  test  further,  and 
notice  whether  liquefaction  takes  place  on  standing. 
A  paste  made  from  a  good  farina  should  not  liquefy, 
but,  on  exposure,  it  should  dry  up.  Inferior  farina 
forms  a  paste  which  will  liquefy  in  two  or  three  days, 
according  to  the  atmospheric  conditions. 

Mineral  Matter. — Mineral  matter  is  almost 
entirely  absent  in  farina.  The  average  amount  found 
by  the  analyses  of  a  large  number  of  samples  was 
o*2  per  cent.  The  percentage  of  ash  may  be  found 
bv  burning  the  farina  in  a  weighed  crucible,  as 
described  on  pages  6 1  and  62,  Mineral  adulteration 
may  be  readily  detected  by  shaking  up  a  portion  of 
the  farina  with  chloroform,  as  described  on  page  63. 

Use  of  Farina  in  Sizing. 

Farina  is  used  chiefly  for  pure  and  light  sizing, 
although  it  may  be  used  in  conjunction  with  sago 
and  maize  for  the  heaviest  sized  goods. 

In  pure  sizing  farina  gives  a  smoothness  and 
pliability  to  the  yarn  which  is  not  excelled  by 
any  other  starch.  The  colour  of  the  cloth  is  also 
whiter  than  when  flour  or  sago  is  used. 

Farina  may  be  used,  without  the  addition  of  any 
other  starch,  for  heavily  picked  goods  if  the  best 
qualities  are  selected,  but,  as  has  been  previously 


Sago  Flour. 


97 


stated,  there  is  a  marked  tendency  for  farina  to  lose 
its  strength,  both  when  mixed  in  the  size  beck,  and 
afterwards  on  the  weavers  beams,  if  the  latter  have 
to  remain  in  the  weaving  shed  for  a  lonor  time.  In 
the  case  of  very  heavily  picked  cloths,  this  is 
always  so,  and  there  is  in  consequence  the  ever 
present  danger  of  the  yarn  becoming  ''soft"  before 
it  is  woven  out. 

In  order.to  reduce  this  tendency  to  "  softening,"  it 
is  advisable  to  use  a  mixture  of  sago  and  farina  for 
all  heavily  picked  goods,  or,  if  farina  be  used  alone, 
^  to  \  per  cent,  of  solid  caustic  soda  should  be  added 
to  the  weight  of  starch  employed,  as  previously 
described  on  page  92.  The  alkali  should  be  dissolved 
in  the  water,  and  the  farina  afterwards  mixed  with  it. 

SAGO  FLOUR. 

Sago  is  the  name  given  to  the  starch  which  is 
derived  from  the  pith  of  several  kinds  of  palms, 
the  principal  of  which  are  : — sagus  rumphii,  sagus 
farinifera,  borassus  flabelliformis,  and  arenga 
saccharifera.  The  palms  are  allowed  to  grow  to  a 
height  of  from  20  to  30  feet,  before  any  of  the  starchy 
matter  is  extracted.  When  the  tree  is  cut  down 
and  the  top  severed  from  it,  it  forms  a  cylinder 
of  about  20  inches  in  diameter,  and  from  15  to  20 
feet  long.  This  cylinder  consists  of  an  outer  woody 
tube  in  which  the  pith  is  enclosed,  Such  a  tree  as 
here  described  will  yield  about  700  pounds  of  starch, 

G 


98        The  Chemistry  and  Practice  of  Sizing. 


and  three  such  trees  would  yield  as  much  starch  as 
one  acre  of  wheat. 

The  starch  is  extracted  from  the  pith,  which  is  a 
mixture  of  starch  and  fibrous  matter,  by  washing, 
etc.,  in  the  manner  described  under  farina. 

When  sago  arrives  in  this  country,  it  generally 
contains  a  quantity  of  foreign  matter  which  it  is 
advantageous  to  eliminate  before  it  is  used  for 
sizing  purposes.  To  effect  this  separation  it  is  usual 
to  dress  or  sieve  the  raw  sago.  The  process  consists 
in  passing  it  through  a  miller's  silk,  by  which  means 
the  foreign  matter  is  removed.  The  sago  is  then 
known  as  ''dressed  sago."  There  are  several  qualities 
of  sago  sold  for  sizing  purposes.  They  vary  both 
in  strength  and  colour.  Sago  contains,  as  a  rule 
about  14  to  15  per  cent,  of  moisture. 

In  determining  the  quality  of  a  sample  of  sago, 
it  should  be  tested  for  consistency  of  paste,  as 
described  on  pages  55  and  56;  for  moisture,  as 
described  on  page  23;  and  for  mineral  matter,  as 
described  on  pages  61  and  62.  This  latter  test  is 
very  necessary,  as  sago  frequently  contains  a  quantity 
of  silica  in  the  form  of  fine  sand.  This  is  a  very 
objectionable  substance  to  have  present  in  a  starch 
like  sago,  which  is  used  almost  entirely  for  light 
sizing.  The  effect  of  this  impurity  would  be  to 
cause  a  rapid  destruction  of  the  healds  and  reeds. 
The  presence  of  gritty  particles  will  be  readily 
detected  when  the   starch  is  being  prepared  for 


Use  of  Sago  in  Sizing. 


99 


examination  under  the  microscope  on  account  of 
the  scratching  effect  shown  when  the  sago  is  rubbed 
up  with  water  on  the  glass  slide  by  means  of  a 
glass  rod. 

Sago  should  also  be  tested  for  chloride  of  sodium 
(common  salt).  The  presence  of  this  substance 
indicates  damage  from  sea  water. 

Use  of  Sago  in  Sizing. 

With  the  exception  of  tapioca,  sago  starch  makes 
a  thinner  paste  than  any  of  the  other  starches  used 
in  sizing.  It  is  used  principally  for  pure  sizing,  and 
more  particularly  for  heavy  picked  goods,  where 
sizing  is  conducted  for  the  purpose  of  giving  the 
greatest  possible  strength  to  the  yarn  with  the  least 
possible  amount  of  size. 

Sago  has  a  greater  tendency  to  strengthen 
the  yarn  than  farina,  and,  unlike  the  latter  starch,  it 
appears  to  be  free  from  the  tendency  to  lose  its 
strength  after  being  mixed.  Yarn  sized  with  sago 
flour  will  retain  its  strength  for  months. 

When  sago  is  used  for  light  or  medium  picked 
goods  it  may  be  mixed  in  the  same  way  as  farina;  but 
when  it  is  required  for  strong  picked  cloths  and  fine 
reeds,  it  must  be  treated  in  a  different  manner 
These  goods  require  a  greater  percentage  of  size  in 
order  to  withstand  the  increased  friction  in  weaving, 
and  consequently  a  stronger  size  must  be  used.  If  a 
strong  mixing  of  sago  be  treated  in  the  same  way 


ioo      The  Chemistry  and  Practice  of  Sizing. 

as  farina,  the  yarns  would  be  rendered  hard  and 
harsh,  with  a  tendency  to  become  brittle.  In  this 
condition  they  would  quickly  destroy  the  healds 
and  reeds  on  account  of  the  cutting  or  filing 
action. 

In  order  to  overcome  this  harshness,  and  con- 
sequently prevent  the  rapid  wearing  of  the  healds 
and  reeds,  it  is  necessary,  in  sizing  the  last  named 
class  of  goods,  to  boil  the  sago  for  a  few  hours  in  the 
beck  before  using  it  in  the  tape  frame.  By  this  means 
a  greater  degree  of  softness,  and  an  increased 
pliability  in  the  yarn  is  obtained,  and  the 
objectionable  properties  of  the  sago  are  destroyed. 
There  is  no  risk  of  sago  size  losing  its  strength 
by  prolonged  boiling,  such  as  occurs  with  farina, 
As  a  matter  of  fact  some  of  the  heaviest  picked 
goods  produced  in  the  cotton  trade  are  sized  with 
strong  sago  mixings,  which  are  kept  boiling  gently 
all  the  day  in  the  beck  from  which  the  taper 
uses  his  size. 

Caustic  soda  may  be  employed  to  advantage  with 
sago.  It  helps  to  break  up  the  granules  into  finer 
particles,  and  besides  making  the  starch  more 
adhesive,  it  also  deepens  the  colour  of  the  mixture. 
This  might  be  objectionable  for  American  yarns,  but 
it  gives  Egyptian  yarns  a  much  better  appearance. 
The  amount  of  caustic  soda  to  use  for  each  ioo 
pounds  of  sago  is  from  \  to  \  a  pound  of  the  solid 
alkali.    The  alkali  should  be  dissolved  in  the  water 


Maize  Flour  and  Maize  Starch.  101 

used  for  making  the  size,  and  the  sago  afterwards 
mixed  with  it. 

For  sizing  coloured  dhootie  borders,  sago  is  much 
more  suitable  than  farina.  This  is  especially  the 
case  where  narrow7  borders  are  being  run,  because 
it  takes  a  long  time  to  use  up  the  size  where  there 
are  a  few  ends  only.  In  consequence  of  this,  the 
strength  of  the  size  in  the  coloured  box  is  gradually 
reduced  on  account  of  the  amount  of  condensation 
which  takes  place.  Not  only  is  the  strength  of  the 
size  reduced  by  condensation,  but  in  the  case  of 
farina  the  prolonged  boiling  would  affect  the  strength 
as  previously  mentioned. 

MAIZE. 

Maize  is  obtained  by  grinding  the  seeds  of  the  zea 
maize.  Like  wheaten  flour  it  is  a  complex  substance, 
consisting  of  starch,  gluten,  sugar,  dextrin,  albumen, 
and  mineral  matter.  The  following  analysis  shows 
the  average  composition  of  maize  flour: — 


Starch   

Gluten   

Cellulose 
Gum  and  Sugar 
Fat  and  Oil  ... 

Ash   

Water   


Per  cent. 

53'S 
8-2 

i3'4 
2-9 

47 
4-8 

12*2 


ios       The  Chemistry  and  Practice  of  Sizing. 

Maize  starch  is  obtained  from  the  ground  maize. 
This  substance  is  not  readily  separated  from  the 
gluten  with  which  it  is  combined,  and,  in  order  to 
effect  the  separation,  it  is  necessary  to  treat  the 
ground  maize  with  some  chemical,  such  as  caustic 
soda,  or  hydrochloric  acid.  These  substances  break 
up  the  combination  and  liberate  the  starch.  The 
starch  may  also  be  separated  by  fermentation,  but 
this  process  is  very  objectionable  on  account  of  the 
disagreeable  smell  produced  by  the  decomposition 
which  takes  place. 

Maize  starch  usually  contains  about  13  to  14  per 
cent,  of  moisture,  and  less  than  one  per  cent,  of  ash. 
It  resembles  farina  in  one  respect,  i.e.,  it  produces  a 
very  thick  paste  on  boiling  with  water.  This  paste 
differs  from  farina  paste  in  being  opaque,  like  that 
obtained  from  wheaten  starch,  whereas  farina  paste  is 
translucent.  Maize  starch  paste  differs  also  in 
character  to  that  obtained  from  wheaten  starch.  In 
the  former  case  the  paste  is  of  a  granular  nature, 
whereas  in  the  latter  case  a  very  smooth  paste  is 
formed  with  the  same  amount  of  boiling. 

Maize  starch  paste  does  not  liquefy  on  standing, 
nor  does  it  lose  strength  after  being  repeatedly 
boiled.  It  is  worthy  of  note  that  this  paste  in  the 
absence  of  antiseptics,  will  mildew,  under  the  same 
conditions,  much  sooner  than  the  paste  made  from 
any  of  the  other  starches; 
"In  determining-  the  qiiality  of  maize  starch,  it 

( 


Use  of  Maize  Starch  in  Sizing,  103 

should  be  tested  for  colour,  as  described  on  page  54; 
for  consistency  of  paste,  as  described  on  pages  55 
and  56;  for  mineral  matter,  as  described  on  pages  61 
and  62;  and  for  moisture,  as  described  on  page  23. 
Maize  starch  varies  considerably  in  colour,  and  for 
sizing  purposes  it  is  advisable  to  employ  a  starch 
of  good  colour. 

Use  of  Maize  Starch  and  Maize  Flour 
in  Sizing. 

Maize  Flour, — Maize  flour  is  used  only 
occasionally  for  sizing  purposes,  In  recent  years 
it  has  been  used  largely  as  an  adulterant  of  wheaten 
flour.  Probably  no  more  unsuitable  substance  could 
have  been  chosen  for  the  purpose,  and  the  authors 
utterly  condemn  the  practice.  The  reason  why  it  is 
not  a  suitable  substance  to  use  for  sizing  purposes 
is  because  it  is  not  easily  gelatinised  by  boiling.  In 
consequence  of  this,  maize  flour  produces  a  dusty 
mixing  because,  in  the  first  place,  the  ungelatinised 
particles  of  flour  possess  little  or  no  adhesiveness, 
and,  in  the  second  place,  on  account  of  their  rough- 
ness, these  ungelatinised  particles  rub  off  when 
subjected  to  the  friction  of  weaving.  A  sizing  flour 
containing  maize  flour  will  not  carry  China  clay 
anything  like  as  well  as  a  pure  flour.  Only  recently 
a  case  came  under  the  writer's  notice  where  a  firm 
of  manufacturers  were  putting  200  per  cent,  of  size 
on  the  twist  in  order  to  get  a  certain  weight  in  the 


104      The  Chemistry  and  Practice  of  Sizing. 

woven  cloth.  The  writer  got  a  greater  weight  in 
the  finished  cloth  with  50  per  cent,  less  size.  The 
result  was  obtained  by  using  a  pure  flour  instead  of 
one  containing  maize  flour,  and  also  by  using  a  better 
China  clay  than  the  one  previously  in  use.  The 
explanation  why  the  mixing  laid  down  by  the  writer 
gave  a  greater  weight  of  size  on  the  cloth  than  the 
one  containing  50  per  cent,  more  size  is  simple. 
In  one  case  the  size  stuck  on  the  yarn,  whereas  in 
the  other  case  it  rubbed  off.  The  change  meant  a 
considerable  saving  to  the  manufacturer  because  he 
got  the  desired  results  at  a  much  less  cost.  The 
unsuitability  of  maize  flour  for  sizing  purposes  is 
further  discussed  under  maize  starch. 

Maize  Starch, — Maize  starch,  or  corn  starch 
as  it  is  very  often  called,  is  used  chiefly  for 
medium  and  heavily  sized  goods,  in  conjunction 
with  wheaten  flour.  A  mixture  of  wheaten  flour  and 
maize  will  give  a  better  appearance,  and  a  harder 
and  firmer  feel  to  the  cloth,  than  can  be  produced 
with  wheaten  flour  alone.  If,  however,  too  much 
maize  starch  be  used  it  tends  to  make  the  yarns 
very  brittle.  Dealers  in  so-called  sizing  flours  use 
maize  starch  very  largely  to  mix  with  wheaten 
flour.  The  proportion  generally  employed  is  three 
or  four  parts  of  wheaten  flour  to  one  part  of  maize 
starch. 

As  previously  stated,  the  authors  do  not  advocate 
the  purchase  of  such  sizing  flours.     It  would  be 


Use  of  Maize  Starch  in  Sizing.  105 


more  preferable  to  buy  a  pure  wheaten  flour,  and 
mix  it  with  maize  starch  as  required.  This  would 
lead  to  better  and  more  economical  results,  and  it 
would  leave  the  manufacturer  quite  independent  of 
the  dealers.  An  instance  of  the  danger  of  this  de- 
pendency upon  the  dealer  in  flour  mixtures  was  shown 
some  years  ago.  A  certain  manufacturer  had  been 
in  the  habit  of  knowingly  buying  his  flour  mixed 
with  20  per  cent,  of  maize  starch.  In  one  delivery 
the  dealer  substituted  maize  flour  for  the  starch. 
The  result  of  using  this  was  that  mildew  developed 
on  the  cloth  sized  with  it.  The  mildew  was  caused 
by  the  maize  flour  not  being  properly  gelatinised 
in  the  boiling  process,  and  in  consequence  the 
chloride  of  zinc  never  got  properly  into  contact  with 
the  starch  granules  of  this  substance.  These 
granules  afterwards  developed  mildew  in  the  form 
of  little  yellow  spots,  and  when  an  examination  of 
these  spots  was  made,  maize  starch  granules  were 
found  in  an  unbroken  state.  This  would  not  have 
happened  had  the  flour  dealer  continued  to  use 
maize  starch  instead  of  substituting  the  maize  flour 
for  it. 

Maize  starch,  itself,  requires  thoroughly  boiling  in 
order  to  ensure  the  proper  breaking  up  and  gelatin- 
isation  of  the  starch  granules,  and  unless  this  boiling 
is  prolonged  the  size  will  produce  a  rough  feel,  and 
a  reedy  appearance  on  the  cloth.  Maize  starch 
must  be  thoroughly  cooked  before  applying  it  to  the 


106      The  Chemistry  and  Practice  of  Sizing, 

yarn,  otherwise  it  is  possible  to  detect,  by  means  of  the 
microscope,  unbroken  granules  of  the  starch  in  size 
which  has  been  washed  from  cloth  containing  it. 

The  best  method  of  treating  maize  starch 
for  medium  and  heavy  sizing,  is  to  boil  it  in  the 
clay  pan  along  with  the  China  clay.  An  improved 
method  would  be  to  add  half-a-pound  of  solid  caustic 
soda,  previously  dissolved  in  a  bucketful  of  water, 
for  each  100  pounds  of  maize  starch.  This  would 
not  only  produce  a  smoother  feel,  but  it  would  render 
the  starch  much  more  adhesive. 

N.B. — Caustic  soda  should  not  be  employed 
where  the  clay  is  boiled  along  with  chloride 
of  magnesium,  as  chloride  of  magnesium  and  caustic 
soda  decompose  each  other. 

Maize  starch  is  not  often  used  in  pure  or  light 
sizing.  In  cases  where  it  is  employed  it  must  be 
boiled  for  at  least  two  or  three  hours  before  it  is 
pumped  to  the  tape  frame.  China  clay  will 
counteract  the  natural  harshness  of  maize  starch  in 
a  light  size  mixing,  but  a  greater  percentage  of  size 
has  to  be  put  on  the  yarn  in  order  to  get  this 
"softness,"  than  would  be  the  case  if  either  farina  or 
sago  were  used  without  the  addition  of  China  clay. 

If  maize  starch  could  be  subjected  to  some 
treatment  which  would  give  it  the  characteristic 
properties  of  wheaten  starch,  there  would  be  a  ready 
market  for  it.  It  has  one  great  advantage,  and  that 
is  its  low  price  as  compared  with  wheaten  starch. 


Tapioca  or  Cassava  Starch. 


107 


There  is  room  for  investigation  in  this  matter,  and 
the  authors  think  that  caustic  soda  could  be  success- 
fully employed  to  get  the  characteristic  "softness." 
without  loss  of  adhesiveness,  if  only  size  mixers 
could  be  trusted  to  neutralise,  or  nearly  neutralise, 
the  excess  of  alkali  required  to  carry  out  the 
operation  successfully,  by  means  of  some  acid  such 
as  acetic  acid,  or  even  sulphuric  acid. 

Experiments  have  been  carried  out  with  the  view 
to  producing  this  "softness"  in  maize  starch  by  first 
treating  it  with  nitric  acid,  and  afterwards  sub- 
jecting it  to  dry  heat.  The  temperature  at  which 
the  operation  is  conducted  must  not  be  high  enough 
to  convert  the  starch  into  dextrin. 

TAPIOCA  OR  CASSAVA  STARCH. 

Tapioca  is  obtained  from  the  roots  of  several 
plants  of  the  genus  manihot,  the  most  important  of 
which  \s  jatropha  manihot,  a  native  of  Brazil.  This 
starch  is  also  known  as  Brazilian  arrowroot. 

Tapioca  has  never  been  used  very  extensively 
for  sizing.  It  produces  a  very  thin  paste  on  boiling 
with  water,  and,  like  farina,  it  loses  strength  with 
prolonged  boiling.  During  1905,  it  was  used 
probably  to  a  greater  extent  than  at  any  other  time. 
This  was  largely  due  to  the  high  price  of  farina,  and 
many  manufacturers  employed  it  as  a  substitute  for 
the  latter  starch,  but  not  writh  any  great  amount  of 
success. 


1 08       The  Chemistry  and  Practice  of  Sizing. 

Tapioca  was  also  used  very  extensively  for  adulter- 
ating farina  and  sago  during  this  period,  and  this 
objectionable  practice  led  to  many  manufacturers 
suffering  considerable  damage.  This  was  especially 
the  case  where  tapioca  was  used  to  adulterate  sago, 
as  in  this  case  the  mixture  was  used  for  pure  sizing 
heavily  picked  goods,  in  which  great  strength  is  a 
most  important  factor.  The  consequence  was  that 
in  many  cases  ''soft  beams"  were  produced,  and  a 
great  deal  of  annoyance  was  caused. 

Tapioca  has  few  claims  upon  the  sizer,  and  the 
authors  merely  give  it  a  place  in  this  volume  because 
it  is  occasionally  used  for  certain  purposes.  The 
chief  use  to  which  tapioca  may  be  put  in  the  textile 
trade,  is  the  production  of  white  dextrin  for  light  fin- 
ishing. For  this  purpose  the  weak  characterof  tapioca 
is  not  objectionable,  because  in  finishing,  the  cloth 
has  not  to  be  subjected  to  any  strain,  such  as  it  under- 
goes in  a  process  like  weaving.  This  is  a  point  many 
people  do  not  realize.  They  think  that  because 
tapioca  is  suitable  for  light  finishing  it  must  be  equally 
suitable  for  a  preparatory  process  like  sizing,  but 
this  is  fallacious. 

RICE  FLOUR. 

Rice  flour  is  prepared  by  grinding  the  seeds  of 
the  rice  plant  " oryza  sativa."  This  substance  is  the 
richest  of  all  the  cereals  in  starch,  but,  like  maize, 
the  starch  is  so  intimately  connected  with  the  gluten 


Use  of  Rice  Flour  in  Sizing,  109 


that  it  requires  the  action  of  chemicals,  such  as 
mineral  acids,  or  caustic  soda,  to  bring  about  a 
separation.  This  separation  of  the  starch  from  the 
gluten  can  also  be  brought  about  by  subjecting  the 
oround  rice  to  fermentation  in  water,  but  the 
process  is  an  objectionable  one.  The  following 
table    shows    the    average    composition    of  rice 


flour  : — 

Per  cent. 

Starch   78'23 

Fat   rv...  074 

Cellulose    3*06 

Gum  and  Sugar   0-45 

Gluten  and  Albumen   6*8o 

Ash    o*8i 

Water   9*91 


IOO'OO 

Rice  flour  is  chiefly  used  in  sizing  for  the  purpose 
of  obtaining  a  harsh  sharp  feel  in  medium  and 
heavily  sized  cloths,  It  is  frequently  mixed  with 
wheaten  flour  by  vendors,  who  make  a  speciality  of 
supplying  4<  sizing  flours  "  for  special  requirements. 
As  previously  stated,  it  is  most  difficult  to  thorough- 
ly break  up  and  separate  the  starch  granules  of  rice 
flour.  It  requires  quite  as  much,  if  not  more,  boiling 
than  maize  flour  or  maize  starch,  to  render  it  fit  for 
giving  good  weaving  results. 

If  rice  flour  be  purchased  ready  mixed  with 
wheaten  flour,  the  process  of  fermentation,  or  of 
steeping   with    chloride    of   zinc,   is  sufficient  to 


no      The  Chemistry  and  Practice  of  Sizing. 

separate  the  starch  granules,  but  the  best  way  of 
treating  rice  flour,  if  it  be  used  at  all,  is  to  buy  it 
separately,  and  mix  the  required  quantity  with  the 
water  in  the  clay  pan.  It  should  then  be  boiled  for 
a  few  hours  with  the  China  clay. 

Where  a  harsh  rough  feel  is  desired  in  the  cloth, 
and  it  is  desirable  to  use  rice  flour  in  conjunction 
with  wheaten  flour  for  its  production,  the  most 
suitable  proportions  are  one  part  of  rice  flour  to 
eight  of  wheaten  flour.  This  mixture  will  give  a 
"feel"  to  the  cloth  which  neither  wheaten  flour,  or 
a  combination  of  wheaten  flour  and  maize  starch 
will  produce. 

RICE  STARCH. 

Rice  starch,  itself,  is  rarely  employed  for  sizing 
purposes.  Rice  flour  is  sufficient  for  all  purposes. 
Rice  starch  is  very  extensively  used  in  laundries  for 
stiffening  collars  and  cuffs.  It  makes  these  goods 
firmer,  and  the  starch  takes  a  higher  polish  than  any 
of  the  other  starches.  This  effect  is  due  to  the 
smallness  of  the  granules  of  rice  starch.  Con- 
sidering the  low  price  of  rice,  it  is  remarkable  that 
dealers  can  maintain  such  high  prices  for  laundry 
starch  in  this  country. 

SOLUBLE  STARCH. 

Soluble  starch,  under  various  fancy  names,  has 
been  put  on  the  market  within  recent  years.     It  is 


Soluble  Starch. 


1 1 1 


manufactured  by  many  different  methods,  and  princi- 
pally from  maize  starch  or  farina,  or  from  mixtures 
of  the  two  starches.  Tapioca  is  also  used  for  its 
production,  either  alone,  or  mixed  with  other 
starches. 

Most  of  the  methods  in  use  for  producing  soluble 
starch  are  patented  processes.  Only  those  which 
are  of  interest  will  be  described. 

One  of  the  earliest  patents  for  the  manufacture 
of  soluble  starch  was  that  of  Kanterowitz  and 
Newstadt,  which  was  granted  in  1895.  The  process 
consists  in  dissolving  starch  in  a  solution  of  caustic 
soda,  afterwards  neutralising  the  alkali  with  sulphuric 
acid,  and  finally  precipitating  the  starch  by  means  of 
sulphate  of  magnesium.  The  precipitated  starch 
is  afterwards  washed  and  dried. 

In  another  process  the  starch  is  treated  with 
dilute  nitric  acid  containing  free  chlorine.  The 
acid  is  removed  by  means  of  a  centrifugal  machine, 
and  the  starch  afterwards  dried  at  about  180°  Fah. 
This  method  was  originated  by  Siemens  and  Halske. 
Other  acids,  such  as  sulphuric,  hydrochloric,  and 
some  of  the  organic  acids,  particularly  formic,  may 
be  substituted  for  the  nitric  acid. 

One  of  the  most  recent  developments  in  this 
direction  is  the  production  of  a  soluble  starch,  to 
which  the  name  of  "  Colloid  "  starch  has  been  given 
by  the  patentees,  Messrs.  Browning  &  Barlow.  This 
starch  is  prepared  by  submitting  various  starches  to 


1 1 2      The  Chemistry  and  Practice  of  Sizing. 


the  action  of  gaseous  acids,  for  certain  definite  lengths 
of  time,  and  at  certain  definite  temperatures,  accord- 
ing to  the  particular  starch  undergoing  treatment. 
The  acid  vapours  are  afterwards  neutralised  with 
gaseous  ammonia. 

Powerful  oxydising  agents,  such  as  hypochlorite 
of  sodium,  persulphate  of  ammonium,  and  chlorinated 
lime,  have  been  used  for  the  production  of  soluble 
starch,  and  patents  have  been  taken  out  for  most 
of  the  processes.  Ozone  has  also  been  employed  for 
rendering  starch  soluble.  In  this  process,  agar-agar 
(a  form  of  sea-weed)  is  the  source  of  the  starch. 
The  agar-agar  is  first  moistened,  and  afterwards 
treated  with  ozone.  The  ozone  is  generated  by  an 
electrical  apparatus. 

Another  process  patented  by  Professor  Dr.  Alex. 
Classen,  in  Aachen,  consists  of  heating  starch  to 
i8o°  F.  under  pressure  in  suitable  vessels  with 
sulphurous  acid  gas,  S02.  The  starch  is  afterwards 
subjected  to  the  action  of  air  or  oxygen,  or  to  some 
liquid  containing  oxygen.  After  being  treated  as 
above,   the    starch    is  again    heated    to    230°  or 

235°  F- 

The  same  Professor  has  also  a  claim  on  a  patent 
process  for  converting  the  cellulose  of  wood  into 
soluble  starch  and  sugar.  In  this  process  the  wood,  or 
other  similar  material,  is  treated  with  water  contain- 
ing chlorine,  and  afterwards  with  sulphurous  acid  gas, 
S02.     Neither  of  these  processes  has  yet  been 


Soluble  Starch. 


113 


successfully  applied  in  practice,  as  they  are  too 
complicated. 

A  new  process  for  preparing  soluble  starch  was 
patented  by  Rellmas  in  1897.  ^  consists  in  treat- 
ing starch  with  a  2  per  cent,  solution  of  either 
sulphuric,  nitric,  or  hydrochloric  acid  at  exact 
temperatures.  The  starch  is  afterwards  washed  to 
free  it,  as  far  as  possible,  from  acid. 

The  objection  to  this  method,  and  to  all  other 
methods  where  acids  are  used,  is  that  great  difficulty 
is  experienced  in  completely  removing  the  last  trace 
of  acid.  If  acids  be  left  in  starch  intended  to  be 
used  for  sizing,  or  for  finishing  dyed  goods,  the 
results  might  be  disastrous. 

Another  objection  to  these  methods  is,  that  it  is 
impossible  to  fix  exactly  the  point  of  chemical 
change  from  ordinary  starch  to  soluble  starch. 
If  the  oxidation  has  gone  too  far  there  is  a  loss 
of  starch  due  to  the  formation  of  sugar  and 
similar  products.  It  is  of  course  essential  that 
there  shall  be  as  little  loss  of  material  as  possible 
in  the  manufacture  of  soluble  starch,  otherwise 
the  product  is  going  to  be  too  costly  to  be  of  any 
practical  use. 

A  recent  process  for  the  manufacture  of  soluble 
starch,  by  the  use  of  which  the  patentees  claimed 
to  be  able  to  effect  great  savings  to  manu- 
facturers, came  under  the  authors'  notice  a  short 

time  ago. 
H 


1 1 4      The  Chemistry  and  Practice  of  Sizing. 

The  process,  which  was  patented  in  this  and 
other  countries,  was  found  to  consist,  when  first 
introduced  by  the  patentees,  in  treating  the  flour  or 
starch  with  a  so-called  secret  solution.  This  solution 
consisted  of  chlorinated  lime  (ordinary  bleaching 
powder),  dissolved  in  water. 

The  bleaching  powder  solution  was  discarded 
after  some  costly  experiments  and  a  solution  of 
hypochlorite  of  soda  was  used  in  its  place.  This 
solution  was  covered  by  a  fresh  patent  and  worked 
in  the  name  of  another  firm.  In  neither  case  is 
the  patent  a  good  one  because  the  authors  made 
the  first  process  public  years  before  the  patentees 
appeared  on  the  scene,  and,  in  the  case  of  the 
hypochlorite  of  soda  solution,  the  writer  gave  the 
secret  to  several  English  firms  of  chemical  manu- 
facturers and  cotton  manufacturers  whilst  the 
patentees  were  still  using  the  bleaching  powder 
solution.  Not  only  is  there  no  patent  right  in  the 
process  but  there  is  absolutely  no  benefit  to  be 
derived  from  it  which  cannot  be  got  in  a  better  and 
cheaper  way.  It  may  have  been  indirectly  successful 
in  some  few  cases,  but  the  same  benefits  could  have 
been  got  by  an  alteration  in  the  proportions  of  the 
ingredients  of  the  size  mixing.  The  explanation  of 
this  is  given  herewith : — A  great  many  manufacturers 
in  Lancashire  are  using  unnecessarily  expensive 
size  mixings,  especially  for  heavy  sizing.  In  most 
cases  the  excessive  cost  of  these  mixings  is  due  to 


Soluble  Starch. 


the  fact  that  too  large  a  proportion  of  flour  or 
starch  is  used  as  an  adhesive  substance  to  carry 
the  China  clay.  When  this  is  the  case  an  excessive 
amount  of  tallow  is  required  to  soften  the  mixing. 
If,  instead  of  using  a  secret  process  (for  which 
exhorbitant  prices  is  asked),  the  manufacturer  would 
reduce  the  proportions  of  flour  or  starch  in  a  given 
mixing,  where  it  is  in  too  large  an  amount,  he  would, 
at  the  same  time,  be  able  to  make  an  enormous 
reduction  in  the  amount  of  tallow  required  to  soften 
the  size. 

The  action  of  bleaching  oowder  solution  and 
hypochlorite  of  soda  solution  on  starch  is  to  convert 
it  into  dextrin.  This  has  the  effect  of  destroying  the 
adhesiveness  of  the  starch  to  a  considerable  extent, 
the  amount  of  destruction  depending  upon  the 
amount  of  solution  employed. 

It  will  be  at  once  apparent  that  if  a  size  mixing- 
contains  an  excessive  quantity  of  flour,  and  a  large 
proportion  of  the  flour  is  destroyed  by  some  treat- 
ment, the  mixing  will  require  less  tallow  to  soften 
it  than  would  be  required  whilst  the  flour  existed  in 
its  original  state.  On  the  other  hand,  if  less  flour  or 
starch  had  been  employed  originally,  less  tallow  could 
have  been  used  to  get  the  same  degree  of  softness. 

The  fact  that  so  many  size  mixings  contained 
flour  and  tallow  out  of  all  proportions  to  what  was 
actually  needed  gave  the  German  process  an  oppor- 
tunity for  success.    Where  the  great  mistake  was 


1 1 6       The  Chemistry  and  Practice  of  Sizing. 

made  was  in  trying  to  use  the  process  in  the  case  of 
properly  proportioned  mixings.  In  such  mixings 
where  the  flour  was  present  in  quantity  sufficient  to 
carry  the  China  clay  and  give  the  necessary  strength 
to  the  yarn  only,  any  destruction  of  the  adhesive- 
ness of  the  flour  would  be  certain  to  cause  trouble, 
because  the  flour  would  not  then  be  sufficiently 
adhesive  to  cause  the  clay  to  adhere  to  the  yarn. 
The  consequences  would  be  the  production  of  clusty 
mixings, lightcuts, and  softbeams  in  the  weaving  shed. 

From  what  has  been  said  it  must  be  evident 
that  it  is  better  to  have  a  size  mixing  put  on  a 
scientific  basis,  than  to  trust  to  some  secret,  haphazard, 
and  costly  process  which  depends  for  its  success  on  the 
destruction  of  the  adhesiveness  of  the  flour.  It  is 
better  to  use  less  flour  in  a  mixing  than  to  use  an 
excessive  amount  and  afterwards  pay  for  its 
destruction  by  some  costly  and  secret  process. 
There  are  no  secrets  in  successful  sizing,  only 
the  application  of  common  sense.  When  the  success 
of  a  mixing  depends  upon  the  dropping  into  it  of  a 
pinch  of  something  carried  in  the  waistcoat  pocket, 
it  may  be  looked  upon  as  merely  "  bluff." 

Soluble  starch  may  be  prepared  by  boiling 
farina  with  a  strong  solution  of  chloride  of  calcium. 
When  properly  prepared  this  substance  is  of  the 
consistency  of  rubber. 

Starch  of  a  more  or  less  soluble  nature  is  formed 
when  strong  solutions  of  chloride  of  magnesium  or 


Soluble  Starch. 


117 


chloride  of  zinc  are  boiled  with  starch.  This 
operation  renders  the  resulant  starch  paste  much 
more  adhesive  than  when  starch  is  boiled  with  water 
alone,  and  chloride  of  zinc  or  magnesium  afterwards 
added  to  it  in  the  ordinary  way  of  mixing. 

The  action  of  the  above  chemicals  has  been 
turned  to  account  by  dealers  in  sizing  ingredients, 
and  there  are  a  great  number  of  special  sizing  sub- 
stances on  the  market  which  are  neither  more  nor  less 
than  starch  boiled  with  one  or  other  of  these  chemicals. 

Soluble  starch  may  be  prepared  by  triturating 
starch  with  sharp  sand  or  broken  glass.  The  result 
of  this  action  is  to  disintegrate  the  starch  granules, 
thus  liberating  the  granulose.  The  granulose  may 
afterwards  be  extracted  with  cold  water. 

Soluble  starch,  as  previously  stated,  may  be 
prepared  by  the  action  of  the  diastase  of  malt  on 
starch.  The  operation  requires  conducting  with 
care,  otherwise  the  starch  is  converted  entirely  into 
dextrose  and  maltose,  substances  which  are  almost 
entirely  devoid  of  adhesive  properties. 

A  sample  of  so-called  soluble  starch,  in  which 
malt  was  the  active  ingredient  used  to  render  the 
starch  soluble,  was  recently  examined  by  the 
authors.  It  was  found  to  consist  of  a  mixture  of 
maize  starch  and  farina,  to  which  finely  powdered 
malt  had  been  added.  The  starch  was  directed  to  be 
steeped  in  hot  water  for  a  short  time  before  using.  A 
remarkable  change  is  found  in  the  properties  of  the 


1 1 8       The  Chemistry  and  Practice  of  Sizing. 


starch  afterthistreatment.  Themixture  boils  thin, and 
it  no  longer  shows  the  reaction  of  starch  with  iodine. 

Previous  to  steeping  in  hot  water,  this  variety  of 
soluble  starch  has  exactly  the  appearance  of  farina  or 
maize  starch  under  the  microscope,  depending  of 
course  upon  which  has  been  used  in  its  manufacture, 
and  no  doubt  this  substance  has  caused  much  trouble 
to  analysts  where  it  has  been  simply  subjected  to  a 
microscopic  examination.  That  it  is  not  simply 
farina  or  maize  starch  may  be  determined  by 
allowing  a  portion  to  steep  at  a  temperature  of  140° 
Fah.,  for  about  an  hour.  A  solution  of  iodine  should 
then  be  added  to  the  mixture,  when  it  will  be  found 
that  it  no  longer  shows  the  starch  reaction. 

It  has  been  found  that  different  starches  require 
different  quantities  of  powdered  malt  to  convert 
them  into  a  soluble  state  when  treated  in  the  manner 
described  on  page  1 15.  Farina  and  tapioca  require 
about  2\  per  cent.,  whilst  maize  starch  and  rice 
require  at  least  5  per  cent.  The  best  method  for 
the  sizer  to  adopt  in  treating  starch  with  malt  in 
order  to  produce  soluble  starch,  is  the  following: — 

The  starch,  to  which  the  powdered  malt  has 
already  been  added,  is  mixed  with  the  required 
quantity  of  water.  The  mixture  is  then  carefully 
heated  until  it  begins  to  thicken,  after  which  the 
steam  is  turned  off,  and  the  mixture  allowed  to  stand 
for  about  12  minutes.  It  should  then  be  boiled 
up  as  quickly  as  possible. 


Soluble  Starch. 


119 


It  is  necessary  to  exercise  the  greatest  care 
where  diastase  in  the  form  of  malt  is  employed  for 
the  purpose  of  producing  soluble  starch,  otherwise 
the  operation  may  be  carried  too  far,  and  the  starch 
will  lose  its  adhesiveness  almost  entirely.  It  is 
advisable  to  digest  the  gelatinised  starch  for  a 
certain  definite  time  for  every  mixing  and  in  this  way 
reduce  the  possibility  of  irregularity  to  a  minimum. 

Although  the  authors  have  given  this  process 
some  prominence,  it  is  doubtful  whether  it  can  be 
applied  with  any  measure  of  success  for  sizing.  There 
are  too  many  chances  of  the  starch  being  spoiled  in 
the  process,  and  it  is  really  beyond  the  powers  of  an 
ordinary  size  mixer  to  get  uniform  results  with  it. 

It  may  be  well  to  point  out  that  the  diastase  of 
malt  has  no  action  upon  the  starch  in  the  presence 
of  chloride  of  zinc,  or  other  powerful  antiseptic. 

Almost  all  the  varieties  of  dry  soluble  starch,  met 
with  by  the  authors,  retain  the  original  form  of  the 
starch  granules,  and  if  alteration  has  taken  place,  it 
is  shown  only  by  a  slight  fraying  of  the  edges. 

The  following  analysis  of  a  sample  of  soluble 
starch  will  show  its  average  composition : — 


Per  cent. 


Starch  

Mineral  Matter 
Water  


067 
2o'o8 


79'25 


IOO'OO 

This  sample  was  free  from  glucose  or  dextrin. 


120      The  Chemistry  and  Practice  of  Sizing \ 


Use  of  Soluble  Starch  in  Sizing. 

Soluble  starch  cannot  be  used  to  the  same 
extent  in  sizing  as  in  "  finishing"  cotton  cloth. 
The  reason  for  this  is  that  the  processes  by  which 
starch  is  rendered  soluble  destroy  its  adhesive 
powers  to  a  very  great  extent.  This  renders  it 
quite  useless  for  the  purpose  of  fixing  mineral 
substances  to  the  yarn,  and  at  the  same  time  reduces 
its  strength-giving  powers  very  considerably.  This 
latter  condition  is  a  matter  of  little  consequence  in 
"finishing"  but  in  a  preparatory  process  like  sizing, 
and  one  which  is  carried  out  for  the  purpose  of 
rendering  the  yarn  suitable  to  undergo  a  manufactur- 
ing process  like  weaving,  it  is  a  most  important 
condition.  From  this  it  will  be  seen  that  the 
ordinary  soluble  starch  of  commerce  is  not  a  suit- 
able substance  to  employ  for  sizing  ordinary  yarns 
where  as  much  additional  strength,  with  as  small  a 
percentage  of  size  as  possible^  is  required. 

If  soluble  starch  be  used  in  sufficient  quantity 
the  requisite  strength  may  be  obtained  from  it,  but 
it  would  be  a  very  expensive  process  to  use  this 
substance  for  sizing  yarns  up  to  40  or  50  per  cent., 
when  China  clay  can  be  used,  in  conjunction  with 
ordinary  starch,  to  get  the  same  strength  and  per- 
centage of  size. 

Soluble  starch  is  useful  for  sizing  strong  yarns, 
such  as  two-fold  yarns,  where  a  moderate  amount  of 
additional  strength  only  is  required,  and  where  the 


Use  of  Soluble  Starch  in  Sizing.  1 2 1 


size  is  used  principally  for  laying  the  fibre  of  the 
yarn  for  the  purpose  of  assisting  in  reducing  the 
friction  in  the  loom.  Soluble  starch  is  also 
particularly  suitable  for  sizing  yarns,  such  as  the 
afore-mentioned,  where  a  very  transparent  size 
is  required. 

Soluble  starch  may  be  used  with  advantage  in 
very  heavy  sizing  for  the  purpose  of  thinning  down 
the  mixing.  This  is  probably  due  to  the  fact  that 
commercial  soluble  starch  generally  contains  a  trace 
of  free  acid.  This  will  act  upon  the  other  starch  of 
the  mixing  and  cause  it  to  boil  thinner  than  would 
otherwise  be  the  case.  The  advantage  to  be  grained 
is,  that  in  thinning  down  a  very  thick  size  it  is 
rendered  less  difficult  to  handle. 

If  some  process  for  the  manufacture  of  soluble 
starch  could  be  introduced  in  which  the  adhesive- 
ness of  the  original  starch  would  be  unaffected,  it 
would  be  of  immense  advantage  in  sizing.  Soluble 
starch  would  then  possess  all  the  advantage  of 
ordinary  starch  for  fixing  mineral  substance  to  the 
yarn,  wTith  the  additional  advantage  of  being  able 
to  penetrate  the  cell  of  the  cotton  fibre,  as  well 
as  filling  up  the  interstices  between  the  fibres  of 
which  a  thread  is  composed.  This  would  give  a 
full  thick  feel  to  the  yarn,  as  well  as  imparting 
additional  strength  for  weaving  purposes. 

Some  three  or  four  years  ago  an  American  firm 
of  starch  manufacturers  used  the  statement  contained 


122       The  Chemistry  and  Practice  of  Sizing. 


in  the  previous  paragraph  for  the  purpose  of  pushing 
the  sale  of  another  of  the  many  forms  of  soluble 
starch.  In  this  case  the  starch  was  prepared  from 
maize  by  a  treatment  which  produced  an  effect  which 
gave  the  product  the  characteristics  of  wheaten 
starch.  When  applied  to  the  yarn  it  had  none  of 
the  harshness  of  size  prepared  from  maize  starch, 
but  gave  the  mellowness  of  wheaten  starch.  The 
preparation  was  put  on  the  market  mixed  with  5  per 
cent,  of  maize  oil,  and  thus  required  no  addition  of 
tallow.  The  one  objection  to  it  was  the  price 
demanded  for  it.  The  Americans  forgot  that 
Lancashire  has  the  whole  world  from  which  it  may 
purchase  its  starch,  and  is  not  confined,  like  the 
United  States  of  America,  to  its  own  productions 
ruled  by  "Trusts." 

This  firm  objected  to  analyses  of  this  preparation 
made  by  the  writer.  In  an  interview  he  was  told 
that  his  certificates,  stating  that  the  starch  was 
prepared  from  maize,  were  all  wrong.  He  was 
informed  that  it  was  prepared  from  wheat,  but  that 
the  processes  to  wThich  it  had  been  subjected  in  the 
preparation  had  given  the  starch  granules  the 
appearance  of  maize  when  examined  under  the 
microscope.  The  writer  suggested  that  if  they 
were  clever  enough  to  make  wheaten  starch  look 
like  maize  there  was  a  more  profitable  field  for  them 
if  they  would  get  out  a  process  which  would  make 
maize  look  like  wheat  under  the  microscope,  seeing 


V 


Dextrin  or  British  Gum, 


123 


that  at  that  time  maize  was  worth  about  ^11  per 
ton  whilst  wheaten  starch  was  worth  about  ^24 
per  ton.     It  was  another  instance  of  "  bluff." 

DEXTRIN  OR  BRITISH  GUM. 

Dextrin  (C6H10O5)  is  produced  from  starch  by 
various  methods  : — 

(1)  By  treating  starch  to  a  temperature  varying 
from  2  1  o° to  280° Cor  360° to  500°  Fah.  This  change 
in  chemical  condition  is  greatly  facilitated, and  brought 
about  at  a  much  lower  temperature,  by  previously 
moistening  the  starch  with  dilute  nitric  acid,  slowly 
drying,  and  finally  subjecting  it  to  a  temperature 
from  about  iio°  to  150°  C.  or  230°  to  300°  Fah. 

(2)  By  boiling  the  starch  with  dilute  hydro- 
chloric acid.  (Continued  boiling  converts  the  starch 
finally  into  glucose), 

(3)  By  treating  starch,  which  has  been  previously 
boiled  with  water  and  allowed  to  cool,  with  malt 
extract,  or  powdered  malt. 

The  first  process  is  largely  adopted  in  the  manu- 
facture of  commercial  dextrin.  This  article  varies 
in  colour  from  a  pure  white  to  a  yellowish  brown ;  as  a 
rule  the  deeper  the  colour  the  more  solublethe  dextrin. 

Commercial  white  dextrin  might  be  more  properly 
described  as  soluble  starch,  containing  as  it  does 
a  large  amount  of  this  substance.  When  examined 
under  the  microscope  it  generally  shows  the  starch 
granules  unchanged,  or  with  only  the  edges  frayed. 


1 24      The  Chemistry  and  Practice  of  Sizing. 

In  some  samples  of  white  dextrin,  however,  the 
granules  are  found  to  be  completely  broken  up,  thus 
making  it  impossible  to  detect  which  particular 
starch  has  been  used  in  its  manufacture.  White 
dextrin  generally  gives  the  same  iodine  reaction 
as  starch,  but  it  is  easily  distinguished  from  starch 
by  its  characteristic  properties. 

The  yellowish  or  light  brown  commercial  dextrins 
are  those  known  as  British  gum.  They  consist 
largely  of  erythro-dextrin,and  their  aqueous  solutions 
give  a  brown  colour  with  iodine.  This  reaction 
however,  is  generally  obscured  by  the  violet  colour 
produced  by  the  starch  present. 

Commercial  dextrin  contains  foreign  matter.  As 
previously  mentioned,  the  white  dextrins  contain 
much  soluble  starch,  and  the  brown  varieties  contain 
more  or  less  glucose.  Dextrin  is  merely  one  of  the 
intermediate  products  in  the  conversion  of  starch 
into  sugar.  Pure  dextrin  can,  however,  be  prepared 
by  dissolving  starch  in  moderately  strong  sulphuric 
acid,  afterwards  quickly  neutralising  the  acid  with 
caustic  soda,  and  precipitating  the  dextrin  with 
alcohol  The  dextrin  obtained  in  this  way  is  free 
from  starch  and  sugar.  Below  is  shown  the  com- 
position of  a  sample  of  brown  commercial  dextrin: — 

Per  cent. 

Dextrin    83*76 

Glucose    4*84 

Water   n'03 

Mineral  Matter   0*37 

IOO'OO 


Appa  ratine.  1 2  5 

Dextrin,  in  the  form  known  as  British  gum,  is 
not  often  used  in  sizing  yarns,  although  it  is  very 
largely  used  in  the  V finishing"  of  certain  classes  of 
cotton  goods.  It  might  be  used  to  advantage,  in 
conjunction  with  farina  or  sago,  for  the  purpose  of 
giving  a  full  feel  to  the  yarn  in  pure  sizing. 

APPARATINE. 

Apparatine  is  the  name  of  a  preparation  which 
is  made  by  treating  starch  with  caustic  soda.  It  is 
a  transparent,  pasty,  and  powerful  adhesive  mass. 
When  dried,  it  has  the  appearance  of  horn. 

Apparatine  is  by  no  means  of  recent  introduction. 
Dipierre,  in  1879,  published  a  recipe  for  its  manu- 
facture, and,  as  a  matter  of  fact,  it  had  been  in  use 
many  years  before  that  time.  The  ingredients  for 
preparing  it,  viz.,  caustic  soda  solution  and  sulphuric 
acid  solution,  are  actually  being  offered  as  patented 
articles  in  Great  Britain  at  the  present  time,  and  the 
vendor  claims  to  be  the  discoverer  of  the  process. 
How  long  sizers  will  go  on  paying  excessive  prices  for 
caustic  soda  and  sulphuric  acid  the  authors  cannot 
say,  but  quote  this  as  another  instance  of  the  foolish- 
ness of  buying  secret  preparations.  There  is  con- 
siderable merit  in  the  product,  when  properly  made, 
but  no  one  has  any  patent  rights  in  it.  The  process 
may  be  applied  most  successfully  to  maize  starch. 
The  caustic  soda  overcomes  the  harshness  of  the 
maize  starch  granule,  and  produces  a  nice  soft  size 


126      The  Chemistry  and  Practice  of  Sizing. 

quite  equal  to  that  obtained  from  farina,  and  without 
the  objectionable  features  of  either  farina  size  or 
raw  maize  starch.  Apparatine  may  be  made  as 
follows  : — 

Sixteen  pounds  of  farina  or  maize  starch  should 
be  mixed  with  7^  gallons  of  water.  To  this  is 
added  gradually,  during  constant  stirring,  4  pounds 
of  caustic  soda  solution  Twaddelling  about  66 
decrees.  In  a  short  time  the  mixture  gelatinises, 
and,  at  the  same  time  becomes  transparent. 
Prepared  in  this  manner,  apparatine  resembles  the 
mucilage  produced  by  mixing  gum  tragacanth  in 
water.  It  does  not  turn  sour  when  exposed  to  the 
air,  nor  will  it  develop  mildew.  It  is  not  possible  to 
use  this  preparation  in  its  strongly  alkaline  form  for 
most  purposes  in  sizing  or  finishing,  it  is  therefore 
necessary  to  nearly  neutralise  the  caustic  soda  with 
sulphuric  acid,  completing  the  neutralisation  with 
acetic  acid.  For  this  purpose  the  following 
quantities,  and  the  methods  of  procedure  given  may 
be  adopted  : — 

Mix  together  in  a  suitable  vessel  100  pounds  of 
maize  or  other  starch,  and  40  gallons  of  water  ;  then 
add  gradually,  with  constant  stirring,  23  pounds  of 
caustic  soda  solution  at  66°  Tw„  and  24  gallons  of 
water.  These  should  be  allowed  to  stand  for  at 
least  two  hours,  and  then  56  pounds  of  sulphuric 
acid  at  about  25°  Tw.  added.  After  standing,  the 
preparation    should  be  tested   for  acid  or  alkali 


Gum  Tragacanth.  127 


by  means  of  litmus  paper.  The  greatest  care  must 
be  exercised  in  seeing  that  no  free  sulphuric  acid 
is  left  in  the  mixture.  In  the  proportions  given 
above  an  excess  of  alkali  will  be  present  in  the 
completed  product.  This  may  be  neutralised  with 
acetic  acid  if  desired ;  any  slight  excess  of  this  acid 
being  removed  on  boiling  the  mixture.  The 
proportion  of  water  mentioned  may  be  varied 
according  to  the  requirements  of  the  sizer. 

Apparatine  is  sometimes  prepared  by  boiling 
maize  starch  with  caustic  soda  and  water,  and  after- 
wards neutralising,  or  nearly  neutralising,  the  alkali 
with  sulphuric  acid.  Prepared  in  this  way  it  requires 
less  caustic  soda,  and  consequently  less  sulphuric 
acid,  in  order  to  produce  results  equal  to  those 
obtained  by  the  cold  process. 

In  preparing  apparatine  the  operator  must 
exercise  the  greatest  care  in  handling  the  chemicals 
employed.  Caustic  soda  will  destroy  woollen  cloth, 
and  sulphuric  acid  is  equally  dangerous  if  it  be 
allowed  to  dry  on  the  fabric.  Both  these  chemicals 
are  likely  to  cause  serious  damage  if  they  come  in 
contact  with  the  eye,  and  the  consequence  of  such 
an  accident  might  result  in  the  complete  loss  of  sight. 

GUM  TRAGACANTH  (Gum  Dragon). 

Gum  tragacanth  is  a  gummy  exudation  from 
astragalus  gummifer,  obtained  by  making  incisions 
in  the  stem  of  the  plant.      It  occurs  in  white  or 


128      The  Chemistry  and  Practice  of  Sizing. 

somewhat  yellowish  flaky  pieces  of  varying  lengths 
and  breadths,  The  pieces  are  thin,  oblong  or 
roundish,  more  or  less  curved,  very  tough,  inodourous, 
and  almost  tasteless.  Gum  tragacanth  usually 
contains  about  60  per  cent,  of  a  substance  which 
yields  pectic  acid  by  boiling  with  water  containing 
hydrochloric  acid.  It  also  contains  about  8  or  10 
per  cent,  of  soluble  gum ;  5  to  6  per  cent,  of  starch 
and  cellulose;  3  per  cent,  of  ash;  20  per  cent,  of 
water;  and  traces  of  nitrogenous  bodies.  The  ash 
is  chiefly  carbonate  of  calcium. 

Gum  tragacanth  is  insoluble  in  alcohol  or  ether, 
and  slightly  soluble  only  in  water.  In  contact  with 
much  water,  however,  it  swells  up,  forming  a  thick 
jelly-like  mucilage.  This  mucilage  gives  the  starch 
reaction  with  iodine.  It  is  coloured  yellow  with 
caustic  soda.  The  gum  is  not  precipitated  by  borax, 
alkaline  silicates,  or  ferric  chloride,  but  it  is  precipi- 
tated by  alcohol. 

The  quality  of  the  gum  may  be  judged  to  a  great 
extent  by  its  colour;  the  whiter  the  colour  the  better 
the  sample. 

Gum  tragacanth  is  not  often  used  in  sizing, 
although  certain  manufacturers  believe  they  get 
some  special  advantage  by  using  it.  If  the 
matter  would  only  be  considered  carefully,  the 
authors  feel  certain  that  gum  tragacanth  would 
disappear  from  sizing  altogether.  In  mixings  where 
it  is  used,  the  amount  of  actual  gum  is  infinitesimal, 


Gum  TragasoL 


129 


and  what  possible  good  results  can  be  expected 
from  this  small  quantity  is  beyond  the  understanding 
of  the  authors. 

Another  objection  to  the  use  of  gum  tragacanth 
is  its  price,  and  when  it  is  known  that  its  properties 
can  be  imitated  to  a  great  extent  by  mixtures  of 
starch  and  white  dextrin,  it  will  be  seen  how 
expensive  a  substance  it  really  is. 

Where  gum  tragacanth  is  used  it  is  necessary  to 
steep  it  for  at  least  a  week  before  mixing  it  with 
the  other  ingredients  of  the  size.  The  mucilage 
ought  really  to  be  passed  through  a  very  fine  sieve, 
in  order  to  remove  minute  particles  of  ungelatinised 
gum.  If  this  process  be  not  carried  out  there  is  a 
danger  of  these  particles  of  the  gum  sticking  to  the 
yarn,  in  the  form  of  flattened  discs,  or  else  they 
are  left  adhering  to  the  finishing  roller  on 
the  tape  frame.  There  is  also  a  danger  of  these 
small  particles  of  gum  developing  mildew,  on  account 
of  not  having  become  impregnated  with  the  proper 
amount  of  chloride  of  zinc. 

GUM  TRAGASOL. 

This  is  the  registered  name  of  a  comparatively 

new  material  for  sizing  and  finishing",  which  is  manu- 

factured  by  the  Gum  Tragasol  Supply  Company 

Limited,  of  Hooton,  and  protected  by  numerous 

patents.    The  gum  is  prepared  from  the  kernel  or 
1 


130       The  Chemistry  and  Practice  of  Sizing. 


seed  of  the  locust  bean,  or  St.  John's  bread,  the 
fruit  of  the  carob  tree,  ceratonia  sihqna. 

The  locust  bean  itself  is  a  valuable  ingredient  of 
prepared  cattle  foods,  but  there  was  little  use  for  the 
hard  kernels  until  it  was  found  that  they  contained 
a  valuable  gum,  the  extraction  of  which  gave  rise 
to  the  present  industry. 

These  kernels  are  found  to  consist  of  three 
distinct  parts: — First,  a  hard  brown  husk;  second, 
two  white  cotyledons;  and  third,  the  germ,  which 
consists  of  two  thin  yellow  layers  separating  the  two 
cotyledons. 

The  portion  of  the  kernel  used  in  the  manufacture 
of  the  gum  is  the  cotyledon,  and  in  order  to  free  it 
from  the  deleterious  brown  husk  and  yellow  germ, 
it  has  to  be  subjected  to  a  prolonged  and  specially 
devised  milling  process. 

When  the  milling  process  is  completed  the  kernels 
resemble  small  white  buttons,  and  consist  almost 
entirely  of  gum  and  woody  fibre.  The  gum  is 
extracted  from  the  milled  kernels  by  cooking  them  in 
steam  jacketed  vats,  until  all  the  gum  has  exuded  ;  by 
this  means  a  thick  mucilage,  consisting  of  gum  and 
woody  fibre,  is  obtained.  This  mucilage  is  filtered  by 
means  of  hydraulic  presses,  and  the  clear  gum 
obtained  is  cooled  by  passing  over  copper  cylinders 
into  jacketed  vats,  through  which  ice-cold  brine  is 
circulated.  It  is  then  mixed  with  a  small  quantity 
of  some  preservative,  such  as  carbolic  acid. 


Gum  TragasoL 


Gum  Tragasol  is  a  stiff,  nearly  transparent,  jelly, 
and,  previous  to  the  addition  of  carbolic  acid,  it  is 
practically  tasteless  and  odourless.  It  is  perfectly 
neutral,  and  from  the  following  analysis,  it  will  be 
seen  that,  although  it  does  not  contain  either  sugar 
or  starch,  it  is  almost  a  pure  carbo-hydrate.  The 
mucilage,  dried  at  212°   Fah.,  has  the  following 


composition: — 

Per  cent. 

Carbon    43*5 1 

Hydrogen    6*23 

Oxygen    48* 38 

Nitrogen    0*39 

Ash    1*49 


Analysts,  Messrs  Stocks  and  White.  ioo'oo 


Tragasol  mixes  readily  with  practically  all  the 
materials  generally  used  in  the  preparatory  finishing 
and  sizing  operations  of  the  textile  trade.  It  con- 
tains a  large  percentage  of  water  owing  to  the 
necessity  of  its  mode  of  extraction  and  manufacture, 
and  were  it  not  so,  its  use  would  be  rendered 
more  difficult  owing  to  its  being  partially  insoluble 
in  water. 

For  most  purposes,  however,  Tragasol  requires 
diluting  with  water  to  prepare  it  for  use.  The  best 
method  is  as  follows: — In  a  suitable  pan  or  mixing 
beck,  preferably  fitted  with  compound  dashers  to 
ensure  perfect  mixing,  place  a  given  quantity  of 
the  gum.  This  is  agitated  for  an  hour  or  two, 
until  it  becomes  more  elastic  in  its  condition.  Cold 


132      The  Chemistry  and  Practice  of  Sizing, 

water  may  now  be  run  in,  very  gradually  at  first, 
until  a  quantity  equal  to  the  gum  has  been  added, 
say  1 1  gallons  to  one  cwt,  of  Tragasol,  or  of  course  a 
larger  quantity  according  to  the  purpose  or  mixing 
required.  During  this  operation  the  gum  absorbs 
the  water,  and,  if  properly  carried  out,  it  is 
left  after  such  dilution  in  a  syrupy  smooth  condition 
not  unlike  thick  oil  or  glycerine. 

Generally  speaking,  the  application  and  use  of  this 
gum  lies  in  the  same  direction  as  the  starches,  but  it 
also  possesses  properties  peculiar  to  itself,  and  which 
may  be  utilized  in  attaining  special  effects  and 
"finishes."  For  sizing,  Tragasol  may  be  looked 
upon  as  an  adjunct  to  flours  and  starches,  combining 
with  them,  and  aiding  in  feeding,  agglutinating,  and 
strengthening  the  yarn.  It  is  also  used  as  a 
carrying  agent  for  fixing  weighting  materials,  such 
as  China  clay,  etc. 

Gum  Tragasol  is  also  used  in  a  number  of  other 
applications  which  are  outside  the  scope  of  the 
present  work. 

ICELAND  AND  IRISH  MOSS 

(Carrageen  Moss). 

These  substances  are  occasionally  used  in 
sizing.  They  owe  their  adhesive  properties  to 
the  "  pectin,"  or  vegetable  jelly,  which  forms  a  large 
proportion  of  the  sea  weed.  The  solution,  obtained 
by  steeping  and  boiling  with  water,  is  gelatinised  by 


Gum  TragasoL  133 


the  addition  of  acids  and  alkalies.  "  Pectin "  is 
precipitated  on  the  addition  of  alcohol.  The  mucilage 
used  for  sizing  may  be  prepared  from  the  sea- 
weed either  by  macerating  in  hot  water  for  twenty- 
four  hours,  and  then  boiling  and  straining,  or  by 
macerating  in  a  solution  of  caustic  soda,  afterwards 
boiling  and  straining,  The  alkali  is  then  neutralised 
with  sulphuric  acid.  By  this  latter  process  a 
mucilage,  superior  in  adhesive  powers  to  the  one 
formed  by  a  treatment  with  water  only,  is  obtained. 

GLUE  AND  BONE  SIZE. 

Glue  is  occasionally  used  for  the  purpose  of 
sizing  yarns.  As  a  rule,  this  substance  is  employed 
for  sizing  two-fold  yarns  where  a  perfectly  trans- 
parent size  is  required. 

Bone  Size  is  an  inferior  form  of  glue,  and  it  is 
principally  employed  in  the  fustian  trade. 


N.B. — Flour  Milling,  together  with  the  pro- 
duction of  farina  and  dextrin,  from  a  commercial 
stand-point,  are  further  dealt  with  in  the  appendix. 

GLUCOSE. 

Although  glucose  possesses  adhesive  powers  the 
authors  propose  to  discuss  this  substance  under 
"  softeners." 


1 34      The  Chemistry  and  Practice  of  Sizing. 


Chapter  II. 

Materials  used  for  giving  weight  and 
body  to  the  Size  and  Yarn. 

CHINA  CLAY,  EPSOM  SALTS,  BARYTES, 
SULPHATE  OF  SODA,  SULPHATE 
OF  LIME,  etc. 


CHINA  CLAY— KAOLIN. 

CHINA  Clay  is  the  most  important  of  all  the 
materials  used  by  sizers  for  giving  weight 
and  feel  to  the  yarn,  It  is  an  almost  pure  hydrated 
silicate  of  alumina,  and  is  produced  by  the  decom- 
position of  mineral  felspar,  a  double  silicate  of  potash 
and  alumina.  When  this  mineral  is  exposed  to  the 
action  of  the  air,  rain,  frost,  and  carbon  dioxide  of  the 
atmosphere,  it  crumbles  to  a  fine  powder.  The  clay 
thus  produced  is  found  mixed  with  various  impurities 
which  must  be  removed  before  it  is  fit  for  use. 

China  clay  is  used  for  a  variety  of  purposes,  and 
different  classes  of  clay  are  required  for  different 
industries.    A  clay  suitable  for  making  into  pottery 


Analysis  of  China  Clay. 


*35 


would  be  quite  unsuitable  for  sizing  purposes,  and 
vice-versa.  The  reason  why  potters'  clay  is  unsuitable 
for  sizing  is  that  it  is  too  plastic,  and  would 
produce  an  unworkably  thick  mixing.  The  lower 
grades  of  clay  are  sold  chiefly  for  making  some 
classes  of  paper.  They  are  similar  in  character  to 
sizing  clays  excepting  that  they  are  not  so  finely 
washed  ;  high  grade  clays  are,  however,  used  for 
coating  paper. 

Usually  more  than  one  quality  of  clay  is  got  from 
one  mine,  and  it  is  in  determining  the  quality  and 
suitability  for  one  purpose  or  another  that  the  expert 
skill  of  the  producer,  ably  assisted  by  the  foreman, 
or  "  captain''  of  the  mine,  is  brought  into  play. 
These  men  have  worked  all  their  lives  in  the  clay 
mines,  and  they  are  able  to  tell  at  once  which 
particular  portion  of  the  clay  bed  being  worked  will 
produce  the  whitest  and  most  suitable  clay  for  sizing. 

The  following  analyses  show  the  composition  of 
two  samples  of  China  clay  of  good  average  quality 
for  sizing  purpose  : — - 


No.  I 
Per  Cent. 


No.  2 
Per  Cent. 


Silica   

Alumina   

Oxide  of  Iron ... 

Lime  

Magnesia  

Potash  and  Soda  Salts 
Water   


4677 

4o*i3 
•38 


114 
1 1  58 


45'89 


4070 


i*49 
1 1  92 


IOOOO 


IOO'OO 


136      The  Chemistry  and  Practice  of  Sizing. 

In  this  country  China  clay  is  found  almost 
exclusively  in  Cornwall  and  Devon.  The  town  of 
St.  Austell  is  the  centre  of  the  industry  in  Cornwall, 
and  about  five-sixths  of  the  total  clay  mined  is  got 
from  this  district.  The  Cornish  clay  is  very  white  and 
more  unctuous  to  the  touch  than  that  found  in  any 
other  part  of  the  world.  It  is  largely  exported  to 
the  Continent  and  to  the  United  States  of  America. 

The  writer  recently  visited  some  of  the  largest 
works  in  Cornwall  with  the  object  of  getting  at  first 
hand  the  details  of  the  modern  processes  involved 
in  the  production  of  China  clay.  Amongst  the  firms 
who  were  courteous  enough  to  permit  an  inspection 
of  their  mines  were  The  West  of  England  China 
Stone  and  Clay  Co.  Ltd.,  Great  Beam  Clay  Co. 
Ltd.,  Hendra  Clay  Co.  Ltd.,  and  Carrancarrow 
Clay  Co.  Ltd. 

One  of  the  most  interesting  sights  in  the  visit 
was  seen  in  the  opening  up  of  a  new  mine.  This 
was  specially  instructive  as  it  gave  an  opportunity  to 
see  the  processes  involved  in  prospecting  for  China 
clay  in  a  way  that  a  visit  to  an  older  mine  could  not 
have  given.  It  is  only  by  such  an  experience  that 
one  is  able  to  realise  the  magnitude  of  such  a  work. 

The  first  essential  is  to  determine  whether  there 
is  a  deposit  of  clay  of  sufficient  area  and  depth  to 
be  worth  working,  as  the  cost  of  opening  up  a  new 
mine  is  very  great.  Trial  pits  are  first  sunk  into 
the  clay  bed,  and  if  they  are  shown  to  be  satisfactory 


Extraction  of  China  Clay. 


137 


a  central  shaft  is  sunk  to  the  bottom  of  the  clay 
deposit,  and  another  one  is  sunk  near  the  outer  edge 
of  the  clay  area.  The  first  shaft  is  called  the 
"  washing  shaft,"  and  the  second  one  is  called  the 
"engine  shaft."  These  shafts  are  connected  at  the 
bottom  by  means  of  a  tunnel  or  "level." 

The  overburthen  or  surface  earth  is  then 
removed  from  around  the  top  of  the  "washing  shaft," 
as  shown  in  the  illustration  on  plate  zi,  and  carried 
by  means  of  wagons,  running  on  rails,  to  a  refuse 
heap  on  the  outskirts  of  the  clay  bed  where  it  is 
deposited. 

After  the  surface  earth  has  been  removed  water 
is  brought  in  to  begin  the  operation  of  washing  the 
exposed  clay.  Gradually  the  clay  immediately 
round  the  "washing  shaft"  is  taken  out,  and  in 
this  way  the  mine  is  being  continually  made 
deeper  and  wider, 

The  processes  involved  in  getting  the  clay  are 
better  seen  in  a  mine  which  has  been  worked  for 
some  time.  The  illustrations  which  follow  will  make 
these  operations  more  clear  to  the  reader  than  a 
written  description  alone  could  possibly  do. 

The  first  operation  consists  in  breaking  up  a 
portion  of  the  bed  of  clay  from  top  to  bottom  by 
means  of  a  "dubber"  or  pick.  A  small  stream  of 
water  is  then  brought  to  the  head  of  the  "stopes" 
or  sloping  sides  of  the  mine,  by  means  of  wooden 
conduits,  and  directed  over  the  area  of  broken  clay. 


138       The  Chemistry  and  Practice  of  Sizing, 


Workmen  agitate  the  water  against  the  dis- 
integrated clay  in  order  to  assist  in  its  removal,  as 
shown  on  plate  iv.  Others  are  employed  in 
breaking  up  the  larger  masses  to  facilitate  the  action 
of  the  water.  The  clay,  together  with  a  large 
quantity  of  gritty  matter,  consisting  of  coarse  grains 
of  quartz,  mica  and  fine  sand,  is  carried  by  the 
water  to  the  bottom  of  the  mine  where  it  is  directed 
into  a  pit  called  a  "sand  drag."  Here  the  coarsest 
particles  are  deposited.  It  is  usual  to  work  two  or 
more  "sand  drags,"  so  that  whilst  one  is  being  filled 
with  the  washings  from  the  clay  bed  the  other  is 
being  emptied  of  the  coarse  deposit  by  workmen. 
This  deposit  is  hauled,  by  means  of  wagons  running 
on  rails,  to  the  top  of  the  mine,  where  it  accumulates 
in  huge  mounds,  as  shown  in  the  illustration  of  the 
Dorothy  mine  on  plate  v.  These  mounds  of 
coarse  quartz  and  sand  are  the  land-marks  of  a 
China  clay  district,  and  there  is  a  fortune  awaiting 
the  individual  who  can  put  this  waste  to  some 
profitable  use. 

From  the  "sand  drags"  the  clay  water  is  allowed 
to  flow  down  the  "washing  shaft,"  and  along  the 
tunnel  previously  mentioned,  to  the  "engine  shaft," 
through  which  it  is  pumped  up  to  the  surface  of  the 
mine  by  means  of  enormous  pumps,  and  carried  by 
means  of  an  earthenware  pipe  to  the  refining 
floors.  The  refining  floors,  of  which  illustrations  are 
shown  on  plates  vi,  vii  and  viiAy  consist  of  a  number 


Extraction  of  China  Clay. 


139 


of  wooden  troughs  or  channels  arranged  parallel  to 
each  other.  These  troughs  are  about  two  feet  wide, 
and  about  200  feet  long. 

The  clay,  in  suspension,  enters  at  the  top  end  of 
the  refining  floors,  and  it  is  distributed  over  the  area  of 
the  channels.  These  channels  are  arranged  with  a 
slight  fall  so  that  the  flow  of  the  clay  water  is  gradual. 
This  allows  the  mica  and  fine  particles  of  sand 
to  fall  to  the  bottom  of  the  troughs  whilst  the 
suspended  clay  is  carried  forward.  A  number  of 
boards  are  placed  along  the  course  of  the  channels 
to  assist  in  collecting  the  deposited  sand  and  mica. 
These  boards  are  called  "traps,"  and  the  coarser 
particles  settle  against  them  whilst  the  finer  clay 
in  suspension  passes  over  the  obstacles  when  the 
liquid  rises  sufficiently  high.  The  coarsest  mica 
and  sand  settles  at  the  place  where  the  pipe  from  the 
works  enters  the  refining  floors,  and  the  deposit  is 
finer  and  finer  as  the  clay  water  reaches  the  outlet  of 
the  channels  to  the  first  settling  ''pits."  As  the 
sediment  accumulates  and  approaches  the  top  of 
the  "traps"  the  inward  flow  of  the  clay  water  from 
the  works  is  suspended  periodically,  in  order  that 
the  accumulation  of  deposited  matter  may  be 
removed  from  the  refining  floors.  This  is  done  by 
removing  a  plug  in  the  bed  of  the  channels, 
and  the  mica  and  sand,  in  the  form  of  a  white 
mud,  is  discharged  through  pipes  arranged  for 
the  purpose.    The  channels  are  then  thoroughly 


140       The  Chemistry  and  Practice  of  Sizing. 

washed  before  more  clay  water  is  pumped  in  from 
the  works. 

The  clay  water,  now  free  from  sand  and  mica 
is  continually  flowing  into  the  first  series  of  "settling 
pits/'  which  are  arranged  at  the  far  end  of  the 
refining  floors.  These  pits  are  built  of  stone,  and  they 
are  generally  circular  or  oval  in  form.  As  a  rule 
they  are  about  thirty  feet  in  diameter  and  about  six 
feet  deep.  At  the  bottom  of  each  "pit"  provision  is 
made  for  letting  out  the  deposited  clay  where  it  has 
settled,  the  clear  water  being  run  off  at  the  top. 
The  outlet  for  the  clay  is  called  a  "hatch,"  and 
it  is  opened  by  means  of  a  valve.  The  clear  water 
is  run  away  into  reservoirs,  from  which  it  is  led  back 
to  the  works  to  be  used  over  again  for  washing  the 
clay. 

After  the  clay  has  settled  in  the  "pits"  for  a 
certain  length  of  time  it  is  run  off  through  the  "hatch" 
previously  mentioned,  and  passes  by  means  of  an 
earthenware  pipe  to  the  final  "  settling  tanks  "  (see 
plate  viii)}  which  may  be  located  close  to  the  works, 
or  they  may  be  three  or  four  miles  away.  These 
"tanks"  are  contiguous  to  the  building  in  which  the 
drying  operation  is  conducted.  If  the  mine  is  near 
to  a  railway  siding  the  drying  chambers  are  close  to 
the  works,  but  if  it  is  some  considerable  distance 
from  the  railway  the  clay  is  run  into  the  final  "tanks" 
by  means  of  the  earthenware  pipe  previously 
mentioned.    This  is  a  more  economical  way  than 


Plate  IV.— Great  Beam  Clay  Mine. 
Washing  Clay  and  showing  how  workmen  break  up  the  Clay  ground. 


Plate  V.— Dorothy  Clay  Mine. 
Showing  how  refuse  is  removed  from  the  "  Sand  Drags  "  and  stacked. 


Extraction  of  China  Clay.  141 


drying  the  clay  at  the  mines  and  carting  it  down  to  the 
railway.  When  the  clay  liquor  reaches  the  final 
"settling  tanks"  it  is  of  the  consistency  of  thick  cream, 
and  contains  about  2\  lbs.  of  clay  per  gallon  of  fluid- 

The  final  "settling  tanks"  are  much  larger 
than  the  "pits."  They  are  usually  about  150  feet 
long,  60  feet  wide,  and  8  feet  deep.  The  clay  is 
here  allowed  to  settle  for  a  period  of  three  to 
six  weeks,  and,  as  the  clear  water  gradually 
rises  to  the  top,  it  is  drawn  off  by  means  of  an 
arrangement  of  plug  holes  in  the  end  of  the  tank. 

After  the  clay  has  settled  sufficiently,  i.e.  about 
the  consistency  of  cream  cheese,  it  is  transferred 
to  the  "dry,"  which  is  a  building  composed  of  two 
parts,  the  "dry"  proper  and  the  "linhay."  The 
"  dry "  is  shown  in  the  illustration  on  plate  ixy 
and  the  "linhay"  on  plate  x.  The  floor  or  pan 
of  the  "dry,"  which  is  constructed  of  porous  tiles 
similar  in  composition  to  fire  bricks,  is  built  on  a 
lower  level  than  the  bottom  of  the  settling  tank  in 
order  to  facilitate  the  tipping  of  the  clay.  The  clay 
is  brought  into  the  drying  chamber  on  wagons  run 
on  rails.  As  the  wagons  are  brought  into  the  building 
they  are  run  on  to  a  travelling  bridge  which  traverses 
the  length  of  the  "dry,"  and  the  clay  is  tipped  and 
spread  over  the  surface  of  the  floor  to  a  depth  of 
about  eight  or  ten  inches.  The  "dry"  is  heated  at 
one  end  by  a  furnace,  and  the  hot  gases  from  this 
furnace  are  carried  by  means  of  flues  underneath 


142       The  Chemistry  and  Practice  of  Sizing. 


the  full  length  of  the  kiln.  Combustion  of  the 
furnace  gases  takes  place  in  the  flues  themselves 
through  the  admission  of  air  at  various  points,  thus 
spreading  the  heat  for  a  considerable  distance  along 
the  flues  from  the  furnace.  The  drying  operation 
takes  from  one  to  several  days,  the  time  depending 
upon  the  position  of  the  clay  in  the  "dry ;"  the  portion 
nearest  the  furnace  being  dried  the  soonest.  The 
water  is  separated  from  the  clay  principally  by 
being  absorbed  by  the  heated  porous  tiles,  and  is 
passed  as  steam  into  the  flues  and  stack  of  the  furnace. 
The  "linhay,"  which  is  illustrated  on  plate  x, 
is  generally  from  six  to  eight  feet  lower  than  the 
drying  chamber,  and  is  used  for  storing  the  dried 
clay. 

Such  in  brief  is  a  description  of  the  processes 
involved  in  the  production  of  China  clay  as  seen  by 
the  writer  at  some  of  the  largest  clay  works  in  the 
world. 

Determination  of  the  Value  of  China  Clay 
for  Sizing  Purposes. 

China  clay  of  the  best  quality  should  always  be 
chosen  for  sizing  purposes.  A  standard  sample 
should  be  kept  for  comparison  with  samples 
submitted  for  sale.  This  sample  should  be  kept  in 
a  well-stoppered  bottle.  China  clay  should  be  tested 
for  grit,  "feel,"  colour,  lime,  iron,  organic  matter, 
and  added  blue. 


Plate  VI. — General  View  of  Trethosa  Clay  Mine,  showing  the  refining  floors, 

settling  tanks,  etc. 


Plate  VII — Refining  Floors,  showing  workmen  clearing  the  deposited  sand,  etc., 

from  the  refining  floors. 


Determination  of  the  Value  of  China  Clay.  143 

Test  for  Grit. — Clay  may  be  tested  roughly 
for  the  presence  of  this  objectionable  impurity  by 
placing  a  little  of  the  sample  between  the  teeth, 
when  any  slight  grittiness  is  at  once  apparent.  A 
better  test,  and  one  that  can  be  made  comparative, 
is  carried  out  as  follows  :  — 

Equal  portions  of  the  clays  under  examination  are 
rubbed  up  into  thin  pastes  with  equal  quantities  of 
water,  in  separate  watch  glasses,  A  small  portion 
of  each  sample  is  then  placed  on  a  smooth  piece  of 
glass  (the  glass  slides  used  for  the  microscopic 
examination  of  starch  are  the  most  suitable),  and  a 
thin  cover  glass  placed  over  it.  The  cover  glass  is 
then  rubbed,  with  gentle  pressure,  on  the  paste, 
when  the  slightest  grittiness  is  at  once  apparent. 
Where  several  samples  are  being  examined,  one 
may  be  readily  compared  with  another.  A  com- 
parison should  be  made  with  the  standard  sample, 
If  the  clay  be  of  a  low  grade,  the  grit  will  be 
perceptible  to  the  fingers,  when  it  is  rubbed  up  with 
water  in  a  watch  glass. 

Grit  in  China  clay  is  objectionable  on  account  of 
its  destructive  action  on  the  healds  and  reeds.  As  a 
matter  of  fact  China  clay  is  employed  not  only  for 
the  purpose  of  adding  weight  to  the  yarn,  but  also 
to  assist  in  softening  the  size  which  would  be  very 
much  harsher  without  its  presence.  In  heavy 
sizing  a  good  clay  is  of  considerable  assistance 
to  the  weaving.     It  can  be  readily  seen,  therefore, 


144      The  Chemistry  and  Practice  of  Sizing. 

how  objectionable  it  would  be  to  employ  a 
gritty  clay. 

The  "Feel"  of  China  Clay. — The  "  feel"  of 
China  clay  is  an  important  point  to  consider  where 
this  substance  is  intended  for  sizing  purposes.  A 
sample  may  be  free  from  grit  and  yet  not  possess 
the  unctuous  "  feel  "  peculiar  to  clay  of  good  quality. 
At  the  same  time  it  is  necessary  to  use  careful  judg- 
ment in  deciding  that  one  particular  clay  is  possessed 
of  a  more  unctuous  "feel"  than  another,  as  very  often 
the  difference  in  this  special  "feel"  is  entirely  due  to 
the  higher  percentage  of  water  contained  in  one  of 
them.  That  this  is  the  case  may  be  readily  seen 
if  a  sample  of  clay  be  dried  for  some  hours,  and 
afterwards  compared  with  a  portion  of  the  undried 
original  sample.  The  dried  portion  will  have  lost  a 
great  amount  of  the  "  feel,"  but  it  will  not  have  lost 
any  of  its  value  for  sizing  purposes. 

If  any  value  is  to  be  placed  upon  the  test  for 
"feel,"  the  experiment  must  be  conducted  with 
China  clay  which  has  been  dried,  and  afterwards 
made  into  a  thin  paste  with  water,  thus  negativing 
the  effect  of  the  extra  moisture  one  clay  may 
contain  over  that  of  another.  For  this  test, 
therefore,  equal  quantities  of  the  standard  sample,  and 
the  sample  under  examination,  should  be  taken  after 
drying,  and  placed  on  smooth  glass  plates  (large 
watch  glasses),  and  equal  quantities  of  water,  sufficient 
to  make  them  into  thin  pastes,  added.     Each  sample 


Colour  of  China  Clay. 


H5 


should  then  be  rubbed  with  the  finger,  and  the 
"feel"  noted.  Some  clays  quickly  absorb  water, 
producing  a  creamy  paste,  whilst  others  separate 
rapidly  from  the  water  with  which  they  are 
mixed. 

Colour  of  China  Clay. — The  colour  of  China 
clay  is  a  most  important  consideration  in  selecting 
this  substance  for  sizing  purposes.  The  sample 
should  be  compared  with  the  standard  sample, 
by  placing  a  small  quantity  of  each,  side  by  side, 
on  a  sheet  of  blue  paper.  When  pressed  flat  the 
difference  in  colour  is  immediately  seen,  especially 
at  the  point  of  contact.  The  test  should  be  carried 
further  by  mixing  samples  of  the  clay  with  water  on 
a  white  plate,  and  comparing  the  colour  after  they 
have  absorbed  water.  The  yellow  tint  in  low  grade 
clays  may  be  due  either  to  iron  or  to  organic  matter, 
but  as  a  rule  it  is  due  to  iron.  Clays  of  bad  natural 
colour  are  frequently  blued,  in  order  to  cover  the 
yellow  tint  and  give  the  desired  whiteness.  When 
the  blue  fades,  however,  the  original  colour  of  the 
clay  will  appear.  Clays  so  treated  should  be  tested 
as  follows  : — 

A  portion  of  the  clay  should  be  divided  into  three 
equal  parts,  and  each  part  should  be  placed  on  a 
watch  glass,  and  made  into  a  paste  with  water. 

A  few  drops  of  strong  ammonia  should  be  added 

to  one  of  the  pastes.    The  second  should  be  treated 

with  a  few  drops  of  bleaching  powder  solution, 
J 


146      The  Chemistry  and  Practice  of  Sizing. 

whilst  the  third  should  be  treated  with  a  few  drops  of 
strong  hydrochloric  acid.  If,  after  these  tests, 
the  pastes  remain  white,  the  clay  may  be  passed, 
but  if  it  be  rendered  brown  or  yellow,  it  should 
be  rejected.  The  objection  to  tinted  clays,  over 
and  above  the  fact  that  they  are  not  of  the  best 
quality,  is  that  the  blue  colour  may  disappear 
when  the  cloth  is  exposed  to  light,  and  the  dark  and 
objectionable  natural  colour  of  the  clay  will  then 
appear. 

The  reagents,  ammonia,  bleaching  powder 
solution,  and  hydrochloric  acid,  are  used  for  the 
purpose  of  detecting  the  presence  of  either  basic  or 
substantitave  aniline  blue,  or  ultramarine  blue. 
Basic  aniline  blues  are  destroyed  by  the  addition  of 
ammonia.  Bleaching  powder  solution,  on  the 
other  hand,  discharges  the  substantitave  colour  as 
well  as  the  basic  colour.  Hydrochloric  acid  destroys 
the  effect  of  ultramarine  blue,  by  decomposing  this 
compound.  As  a  matter  of  fact,  basic  aniline  blue 
is  almost  invariably  used  for  tinting  China  clay, 
because  it  gives  a  brighter  appearance  to  the  clay 
than  a  substantitave  colour,  and  it  is  easier  to  use 
than  ultramarine  blue.  A  China  clay  of  good 
natural  colour  should  be  affected  slightly  only  by 
either  of  the  above  tests. 

It  will  be  as  well  to  warn  manufacturers  that 
whiteness  in  clay  is  not  always  an  index  of  its 
suitability  for  sizing  purposes.    There  are  some  very 


Plate  VIIa. — Showing  Clay  Stream  from  mine  entering  refining  floors. 


Plate  VIII.— Final  Settling  Tanks,  showing  entrance  to  the 


Iron  in  China  Clay. 


147 


white  clays  which  are  exceedingly  gritty.  It  is 
necessary,  therefore,  to  judge  the  value  of  a  clay 
for  sizing  purposes  by  the  application  of  other  tests 
than  that  for  colour  only. 

Test  for  Lime. — China  clay  should  be  free 
from  chalk  or  limestone  (carbonate  of  calcium).  The 
presence  of  this  substance  is  detected  by  adding  a 
small  quantity  of  hydrochloric  acid  to  the  sample. 
If  carbonate  of  calcium  be  present  effervescence 
occurs,  and  the  calcium  passes  into  solution  as  CaCl2. 
The  presence  of  calcium  may  be  further  confirmed  by 
testing  this  solution  in  the  usual  way. 

Test  for  Iron. — Iron  is  sometimes  found  in 
China  clay  in  sufficient  quantity  to  damage  cloth  by 
developing  iron  stains.  The  following  test  should 
therefore  be  applied  : — 

Equal  quantities  of  the  standard  clay  and  the 
sample  should  be  mixed  in  separate  watch  glasses 
with  sufficient  water  to  form  thin  pastes.  Two 
drops  of  pure  concentrated  hydrochloric  acid  should 
be  added  to  each  sample  and  well  stirred  into  the 
mixtures.  They  should  then  be  allowed  to  stand 
for  five  minutes,  and  at  the  end  of  that  time,  exactly 
two  drops  of  a  very  dilute  solution  of  ferrocyanide 
of  potassium  should  be  added  to  each.  If  iron  be 
present  a  blue  colour  will  be  developed,  varying  in 
intensity  according  to  the  amount  of  iron.  Most 
samples  of  China  clay  will  give  a  faint  shade  of  blue 
with  this  test,  but  in  some  cases  the  colour  is  very  deep. 


148       The  Chemistry  and  Practice  of  Sizing. 

Another  test,  which  is  sometimes  useful,  is  to  mix 
equal  quantities  of  the  standard  sample,  and  the 
clay  to  be  examined,  with  equal  quantities  of  water, 
and  allow  them  to  stand  for  several  days.  In  clays 
contaminated  with  iron,  a  brownish  shade  is  produced 
by  this  exposure.  Such  a  sample  should  never  be 
used  in  sizing. 

Acids  in  China  Clay. — Mineral  acids  are 
occasionally  employed  for  improving  the  colour 
of  China  clay.  Providing  every  trace  of  acid 
is  removed  by  washing  there  is  no  objection  to 
the  use  of  a  clay  so  treated.  At  the  same 
time  the  greatest  care  should  be  exercised  in 
the  selection  of  China  clay  for  sizing  purposes, 
because  the  presence  of  free  mineral  acid  would 
have  most  objectional  consequences.  It  would 
weaken  the  size  when  boiled,  by  converting  the 
starch  into  sugar,  and  it  would  cause  the  reeds  in 
the  looms  to  rust,  and  so  cause  iron-stains  on  the 
cloth.  Every  consignment  of  Clay  should  be  tested 
for  the  presence  of  mineral  acids. 

Use  of  China  Clay  in  Sizing. 

A  good  clay,  especially  for  heavy  sizing,  is  as 
important  as  a  good  flour.  China  clays  differ  so  much 
in  their  physical  properties  that  variations  in  sizing 
results  may  arise  if  a  clay  different  from  the  one  in 
general  use  be  substituted,  even  when  they  are  each 
of  excellent  quality.   Some  China  clays  give  excellent 


Plate  IX— The  interior  of  the  "dry"  or  Clay  Kiln,  showing  electric  travelling  bridge. 
The  West  of  England  China  Stone  &  Clay  Co.  Ltd. 


Use  of  China  Clay  in  Sizing. 


149 


results  for  light  and  medium  sizing,  and  yet  they  are 
unsuitable  for  heavy  sizing,  owing  to  some  peculiarity 
they  possess  which  renders  the  yarns  harsh.  On 
the  other  hand,  certain  clays  will  answer  equally  well 
for  light,  medium,  or  heavy  sizing.  As  a  matter  of 
fact,  the  failure  to  produce  a  well  "sized"  shirting  is 
very  often  entirely  due  to  the  use  of  unsuitable 
China  clay.  The  authors  recommend  the  use  of  a 
"special  superfine"  clay  for  all  classes  of  sizing, 
The  difference  in  cost  over  an  inferior  and  low 
priced  clay  is  more  than  made  up  by  the  results. 
Not  only  are  better  results  obtained  in  weaving,  and 
in  the  feel  and  appearance  of  the  cloth,  but  there 
is  not  the  same  wear  and  tear  on  the  healds 
and  reeds.  A  better  looking  and  brighter  cloth 
is  obtained  by  using  a  high-class  clay,  and  there 
is  less  "dusting  off"  in  the  weaving  shed  and 
warehouse. 

Different  samples  of  China  clay  vary  very  greatly 
also  in  the  amount  of  water  they  require  to  make  a 
heavy  mixing.  It  is  very  often  the  case  that  the  clay 
which  requires  the  least  amount  of  water  makes  the 
thinnest  mixing.  The  authors  have  seen  mixings 
made  to  put  on  from  150  to  160  per  cent,  of  size 
vary  in  specific  gravity  as  much  as  the  equivalent  of 
50°  Tw.  There  has  also  been  a  great  difference  in  the 
weaving  results  ;  the  thinner  mixing  producing  a 
harsh-feeling  brittle  yarn,  whilst  the  thicker  mixing- 
produced  a  smooth  pliable  yarn  having  good  weaving 


1 50       The  Chemistry  and  Practice  of  Sizing. 

qualities.  From  this  it  will  be  seen  how  essential  it  is 
to  have  a  suitable  clay  of  good  weaving  properties,  and 
one  which  is  regular  in  quality.  Where  a  mixing  is 
given  it  is  very  necessary  that  the  nature  of  the  clay 
intended  to  be  used  should  be  known;  otherwise  the 
results  desired  may  not  be  attained.  The  clay  used 
by  the  authors  for  the  mixings  described  in  the 
section  on  practical  sizing,  was  obtained  from  The 
West  of  England  China  Stone  and  Clay  Co., 
and  the  quantities  of  the  various  ingredients  are 
based  upon  the  use  of  this  one.  The  authors 
do  not  wish  to  suggest  that  there  are  no  other 
suitable  clays  on  the  market,  but  in  laying  down 
a  mixing  it  is  necessary  to  have  some  standard 
as  a  basis,  otherwise  unexpected  results  will  be 
obtained. 

Method  of  Mixing  China  Clay. 

It  is  usual  in  sizing  to  boil  China  clay  for 
periods  ranging  from  one  to  six  hours,  the  exact 
time  depending  upon  the  class  of  mixing  in  course 
of  preparation. 

The  sole  object  of  boiling  China  clay  is  to  bring 
about  a  separation  of  the  particles  of  clay  as 
thoroughly  as  possible. 

In  light  and  medium  sizing,  where  the  quantity 
of  water  used  is  fairly  large  as  compared  with  the 
weight  of  China  clay,  it  will  not  be  necessary  to  boil 
as  long,  in  order  to  effect  the  separation  of  the  clay, 


Use  of  Powdered  China  Clay  in  Sizing.  151 

as  it  is  in  heavy  sizing,  where  these  conditions  are 
reversed. 

Although  boiling  is  looked  upon  as  the  only 
correct  method  for  treating  China  clay,  previous 
to  its  admixture  with  the  other  ingredients  of 
the  size,  the  authors  are  firmly  convinced  that  this 
method  is  not  the  best  one  to  employ.  It  is  a 
different  matter  with  starch.  This  substance  has  to 
be  boiled  in  order  to  break  up  the  starch  granules 
into  as  fine  particles  as  possible  by  gelatinisation. 
In  China  clay,  however,  there  are  no  granules  to 
gelatinise,  the  particles  of  clay  being  simply  held 
together  by  the  moisture  contained  therein.  That 
this  is  the  case  is  shown  by  drying.  In  the  dried 
state  it  will  be  found  to  be  much  easier  to  reduce 
to  a  fine  powder  than  in  the  undried  state.  It  will 
also  be  found  that  the  powdered  clay  will  mix  much 
more  readily  with  water  than  clay  in  its  unbroken 
state.  It  stands  to  reason,  therefore,  that  if  dry 
powdered  clay  were  used,  instead  of  damp  lumpy  clay, 
there  would  be  no  necessity  for  prolonged  boiling 
with  water.  By  way  of  putting  this  to  a  practical 
test,  the  following  experiment  was  made  : — 

A  quantity  of  China  clay,  sufficient  to  make 
several  mixings,  was  put  through  a  disintegrator — 
a  machine  similar  to  the  one  used  for  grinding 
the  solid  colours  in  the  manufacture  of  paint.  This 
operation  converted  the  China  clay  into  a  fine 
powder.      In    this    condition    a    portion    of  the 


152       The  Chemistry  and  Practice  of  Sizing. 

clay,  sufficient  for  one  mixing,  was  added  to  the 
necessary  quantity  of  water,  tallow,  and  chloride  of 
magnesium.  This  mixture  was  heated,  in  order  to 
melt  the  tallow,  and  afterwards  mixed  with  the 
starchy  matter  and  the  chloride  of  zinc.  This 
completed  the  mixing  without  requiring  any  boiling 
previous  to  its  being  pumped  to  the  tape-frame. 
Treated  in  this  way  the  mixing  produced  a  better 
looking  cloth,  and  the  yarns  sized  with  it  wove 
better,  than  was  the  case  with  a  similar  mixing1  in 
which  undried  and  unpowdered  clay  had  been  boiled 
for  four  hours  in  the  usual  way. 

The  remainder  of  the  powdered  China  clay  wTas 
used  for  other  classes  of  mixings,  and  in  every  case 
the  yarn  sized  with  them  were  better,  and  the  woven 
cloth  was  better  in  appearance  than  where  ordinary 
China  clay  was  used,  and  mixed  in  the  usual  way. 

From  this  it  will  be  clearly  seen,  therefore,  that 
where  large  quantities  of  China  clay  are  used,  a  con- 
siderable saving  of  time  and  also  of  steam  could  be 
effected  if  the  clay  could  be  bought  dried  and 
ground  instead  of  in  a  lumpy  condition.  In  the 
latter  case  steam  is  required  for  the  purpose  of  boil- 
ing the  clay  for  an  average  of  at  least  three  hours 
for  each  mixing.  This  has  to  be  cooled  sufficiently 
to  allow  the  starchy  matter  to  be  added.  Thus, 
in  heavy  sizing,  at  least  six  to  eight  hours  are 
required  to  make  a  mixing,  and  steam  has  to  be  used 
for  at  least  three  hours.     If  the  China  clay  were 


Use  of  Powdered  China  Clay  in  Sizing,      \  53 

purchased  in  a  state  of  fine  powder  it  would  be 
possible  to  reduce  the  time  occupied  in  making  a 
heavy  mixing  by  at  least  four  to  six  hours,  as  well 
as  to  save  at  least  75  per  cent,  of  the  steam  which  is 
at  present  employed  in  boiling  the  clay.  Not  only 
would  this  be  the  case,  but  the  results  would 
be  more  satisfactory  -  than  under  the  present 
conditions. 

The  making  of  a  mixing  would  be  very  much 
simplified  in  the  case  of  medium  sizing,  where  a 
starch  like  farina  is  employed,  instead  of  wheaten 
flour.  The  method  of  procedure  in  this  case 
would  be  as  follows  : — 

The  water,  chloride  of  magnesium,  and  chloride 
of  zinc  should  be  put  together  in  the  mixing  pan. 
The  whole  of  the  starchy  matter  should  then  be 
added,  and  agitated  for  half-an-hour,  in  order  to 
ensure  the  separation  of  the  starch  granules.  The 
clay  and  tallow  should  then  be  added,  and  the  whole 
heated  until  the  tallow  melts,  in  which  condition  it 
readily  becomes  incorporated  with  the  other  in- 
gredients of  the  size. 

It  would  not  be  practicable  to  set  up 
suitable  plant  for  powdering  China  clay  in  every 
sizing  establishment,  but  the  matter  is  well  worth 
the  consideration  of  every  sizer,  and  it  would  pay 
some  China  clay  merchant  to  take  the  matter  up. 
The  authors  are  certain  that  the  pioneer  in  this 
movement  would  be  amply  recompensed  by  his 


154       The  Chemistry  and  Practice  of  Sizing. 


increased  sales  as  soon  as  the  advantages  of  using 
powdered  China  clay  became  known. 

EPSOM  SALTS— SULPHATE  OF 
MAGNESIUM. 

This  substance  is  prepared  chiefly  from  kieserite, 
a  mineral  found  as  a  natural  deposit  at  Stassfurt,  in 
Prussia, 

Kieserite  is  composed  of  a  mixture  of  sulphate 
of  potash,  soda,  and  magnesia.  It  is  chiefly  worked 
for  its  potash  salt,  which  is  by  far  the  most 
valuable  constituent. 

Epsom  salts  occur  generallyin  the  form  of  needle- 
shaped  crystals.  These  crystals  contain  more  than 
half  their  weight  of  water,  as  shown  by  the  follow- 
ing formula  MgS04,  7H20.  The  proportion  of 
actual  sulphate  of  magnesia  to  water,  is  1 2  of  the 
former  to  12  '6  of  the  latter. 

Epsom  salts  are  used  very  largely  as  a  weighting 
ingredient  for  sizing  yarns  in  certain  districts, 
particularly  in  "  ball  sizing."  This  substance  is  also 
extensively  used  in  "finishing,"  for  such  goods  as 
flannelettes,  Oxford  and  Harvard  shirtings,  shoe 
linings,  etc. 

For  4' finishing"  purposes  it  is  essential  that  the 
Epsom  salts  be  free  from  chloride  of  magnesium, 
otherwise  there  is  a  risk  of  damage  occuring.  The 
presence  of    chloride  of    magnesium    is    of  no 


Epsom  Salts — Damage  from  use  of.  155 

consequence  where  the  salts  are  used  for  sizing,  as 
chloride  of  magnesium  is  invariably  an  ingredient  of 
the  size,  and  a  little  more  or  less  would  make  no 
material  difference  in  the  results.  The  authors 
mention  this  fact  because  it  has  been  stated  so  often 
that  a  trace  of  chloride  of  magnesium  is  dangerous 
in  Epsom  salts  used  for  sizing  purposes. 

W.  Thomson,  in  his  book  on  sizing,  published 
in  1879,  and  which  was  for  many  years  the  only 
valuable  manual  on  the  subject,  describes  a  case  of 
damage  to  Oxford  shirtings.  This  matter  is  of  con- 
siderable interest,  and  the  authors  quote  the  case 
as  stated. 

A  certain  firm  shipped  Oxford  shirtings,  the 
same  in  quality,  and  made  at  the  same  time,  but 
finished  by  three  different  finishers.  These  pieces 
were  packed  indiscriminately  in  bales,  and  a  number 
of  them  were  returned,  some  damaged  and  others 
undamaged.  The  only  difference  between  the 
damaged  and  undamaged  pieces  from  a  physical 
examination  was  that  the  former  were  tender  and  the 
latter  were  not,  the  colour  being  uninjured.  Had 
the  injury  been  caused  either  by  free  acid  or  mildew, 
some  of  the  colours  would  have  been  injured;  but 
as  a  matter  of  fact,  the  damaged  pieces  were  practic- 
ally free  from  acid,  and  no  trace  of  fungus  growths 
could  be  found.  A  most  marked  difference,  however, 
was  shown  by  chemical  analysis.  Each  contained 
chloride  as  well  as  sulphate  of  magnesium,  but  all 


1 56      The  Chemistry  and  Practice  of  Sizing. 

the  damaged  pieces  contained  a  much  larger 
quantity  of  the  chloride  than  the  undamaged.  The 
following  ogives  the  ratio  of  chloride  of  magnesium 
to  sulphate  per  centum  in  each  sample: — 

Damaged.  Undamaged. 

Crystallized  Sulphate  of  Magnesium  ...  86*8   98*11 

„  Chloride  of  ...  13*2   ....  1*89 

IOO'OO  IOOOO 


It  seemed  then  that  chloride  of  magnesium  was 
capable  of  tendering  cloth  by  reason  of  some  physical 
action;  and  various  experiments  were  made  with  a 
view  of  testing  this  point.  It  is  well  known  that  if 
a  piece  of  cloth  be  steeped  in  a  solution  of  sulphate 
of  magnesia,  taken  out,  and  the  salt  allowed  to 
crystallize  in  the  fabric,  the  latter  will  be  more  or 
less  slightly  tendered;  and  if  the  salt  be  washed 
out,  and  the  cloth  again  dipped  into  the  solution,  and 
the  salt  allowed  to  crystallize  in  it,  the  cloth  will  be 
still  further  tendered;  and  if  this  be  done  repeatedly 
the  cloth  would  become  as  weak  as  tinder. 

The  question  then  suggested  itself  whether 
chloride  of  magnesium  might  not  produce  a  very 
similar  effect,  and  by  experiment  it  was  found  that 
it  would  do  so.  The  chloride  being  a  very  delique- 
scent salt,  would,  especially  in  damp  weather,  remain 
in  the  fabric  as  a  liquid,  and  as  such  would  dissolve 
some  of  the  Epsom  salts ;  but  if  the  weather  became 
colder  or  drier,  or  both,  the  " salts"  alone,  or  in 


Epsom  Salts — Damage  from  use  of.  157 

company  with  the  chloride  of  magnesium,  would 
crystallize  in  the  fibre,  and  in  so  doing  would  expand 
in  the  filaments  of  cotton  and  rupture  them. 

This  action  of  crystallization  and  solution,  so  far 
as  the  heat  and  cold  are  concerned,  can  be  observed 
in  the  storm  glass,  where  in  cold  weather  the  glass 
seems  nearly  full  of  crystals,  whilst  in  warm  weather 
only  a  few  can  be  observed  at  the  bottom  of  the 
liquid.  The  damage  above-mentioned  was  therefore 
clearly  traced  to  this  peculiar  action.  It  is  question- 
able, however,  whether  this  action  could  take  place 
except  where  the  goods  were  heavily  weighted  with 
sulphate  of  magnesium,  and  contained  a  considerable 
percentage  of  the  chloride  f 

In  quoting  the  above,  the  authors  do  so  for 
several  reasons.  The  question  of  danger  from  the 
use  of  Epsom  salts  in  conjunction  with  chloride  of 
magnesium  is  one  which  is  frequently  brought  for- 
ward, and  whilst  we  agree  with  the  conclusion  in  the 
particular  case  of  Oxford  shirtings  quoted,  we  do  not 
agree  with  the  statement  that  "this  action  could  only 
take  place  where  the  goods  were  heavily  weighted 
with  Epsom  salts,  and  contained  a  considerable  per- 
centage of  the  chloride."  Practical  experience  points 
to  the  opposite,  and  shows  that  where  a  large  pro- 
portion of  chloride  of  magnesium  is  present,  sulphate 
of  magnesium  does  not  tender  the  cloth.  It  is 
common  knowledge  that  large  quantities  of  Epsom 
salts  are  used  regularly  in  conjunction  with  chloride  of 


158       The  Chemistry  and  Practice  of  Sizing. 

magnesium  in  sizing,  and  no  damage  has  ever  been 

known  to  occur.     The  following  mixing  has  been 

used  for  many  years  without  tendering  taking  place, 

and  it  is  only  one  of  many  known  to  the  authors: — 

Flour   6|  bags  (2801b.  per  bag). 

China  Clay    sh  bags  (2241b.  per  bag). 

Tallow   324  lb. 

Epsom  Salts   5  cwt. 

Chloride  of  Magnesium   54  gallons  at  6o°T. 

Chloride  of  Zinc   25  gallons  at  i02°T. 

It  will  be  seen,  therefore,  that,  notwithstanding 
the  statement  of  Mr.  Thomson  referred  to  on  page 
157,  so  large  a  relative  proportion  as  30  per  cent,  of 
chloride  of  magnesium  to  70  per  cent,  of  Epsom 
salts  may  be  used  without  ill  effects  resulting. 

In  the  opinion  of  the  authors  the  danger  from 
the  chloride  of  magnesium  is  when  it  is  present  only 
in  small  quantities  as  an  impurity  in  the  Epsom 
salts  used  in  "finishing,"  but  never  when  it  is  used  in 
large  quantities  in  sizing,  especially  where  there  is 
also  present  a  large  quantity  of  such  a  powerful 
deliquescent  substance  as  chloride  of  zinc. 

The  damage,  produced  in  the  case  quoted,  was 
probably  due  to  the  small  proportion  of  chloride  of 
magnesium  present.  This  would  allow  the  Epsom 
salts  to  crystallize  under  certain  atmospheric  con- 
ditions, and  re-dissolve  under  others,  whereas  in 
sizing,  where  a  large  proportion  of  chloride  of 
magnesium  is  present,  the  yarns  are  kept  in  a  moist 
condition(a  condition  not  desired  in  "finished"  goods). 


Epsom  Salts — Damage  from  use  of.  159 

In  spite  of  the  theory  of  the  cause  of  damage  in  the 
above-mentioned  case,  it  is  a  matter  of  fact,  that 
large  quantities  of  flannelettes,  shoe  linings,  etc.,  are 
" finished"  with  Epsom  salts  in  conjunction  with 
chloride  of  magnesium  and  glucose,  and  the  authors 
have  never  come  across  a  case  of  damage  which  could 
be  attributed  to  this  cause.      The  chief  risk  from 
the  presence  of  chloride  of  magnesium  in  " finished" 
goods    is,    that    during    the    drying  process,  the 
chloride  of  magnesium  may  be  decomposed  with 
the  formation  of  free  hydrochloric  acid.    This  would 
tender   the   fabric.      There    is    more    danger  of 
damage  from  this  cause  in  " finishing,"  than  there 
is  in  sizing.     The  reason  for  this  is  two-fold.  In 
the  first  place,  "finished"  goods  have,  as  a  rule,  been 
bleached,  and  this  renders  them  more  susceptible  to 
the  action  of  free  acid  than  grey  yarn  which  has 
not  lost  its  protective  coating  of  waxy  and  oily 
substances.     In  the  second  place,  the  drying  oper- 
ations in  ''finishing"  are  very  different  to  the  drying 
operations  in  sizing.     In  the  former  case,  the  cloth 
passes  over  a  large  number  of  drying  cylinders, 
whereas  in  the  latter  case  the  yarn  passes  over  not 
more  than  two.      The  effect  of  drying  by  means  of 
a  large  number  of  heated  cylinders  is  more  severe 
than  where  the  yarn  passes  over  two  only,  as  the 
first  three  or  four  cylinders  practically  remove  the 
excess  of  moisture,  and  the  remainder  are  employed 
in  heating  an  almost  dry  fabric.    This  is  not  the  case 


1 60      The  Chemistry  and  Practice  of  Sizing. 

when  yarns  are  dried  on  the  tape  frame  ;  the  object 
of  the  taper  being  to  remove  the  excess  of  moisture 
only,  and  not  to  over-dry  the  yarns.  It  will  be 
readily  seen  from  this,  therefore,  that  although  there 
is  danger  of  damage  from  the  presence  of  chloride 
of  magnesium,  by  over-drying  in  "finishing,"  there 
is  no  danger  where  the  drying  operation  is  conducted 
with  the  object  of  removing  the  excess  of  moisture 
only. 

Nearly  all  Epsom  salts  contain  a  small  quantity 
of  chloride  of  magnesium.  It  may  be  detected 
by  dissolving  a  little  of  the  salt  in  water,  and  adding 
a  few  drops  of  nitric  acid  and  a  few  drops  of  a  solu- 
tion of  nitrate  of  silver.  The  quantity  of  white  curdy 
precipitate  which  forms  is  a  rough  indication  of  the 
amount  of  chloride  present.  Comparative  tests  may 
be  made  by  keeping  as  a  standard  the  sample  which 
shows  the  least  precipitate,  and  changing  the 
standard  when  a  better  one  is  obtained.  Care  should 
be  taken  to  use  the  same  quantity  of  Epsom  salts 
in  each  case,  and  for  this  purpose  a  small  measure 
should  be  kept,  or  a  definite  weight  should  be  dis- 
solved in  a  definite  measure  of  water,  and  the  same 
quantity  of  nitrate  of  silver  solution  used  for  each 
test.  Students  who  possess  the  necessary  know- 
ledge will  of  course  test  for  the  amount  of  chloride 
of  magnesium  in  the  usual  way. 

Epsom  salts  is  a  good  filling  material  It  is  very 
soluble  in  water,  and  in  consequence  it  is  readily 


Sulphate  of  Soda — Glauber  s  Salts.        1 6 1 


absorbed  by  the  fibre,  thus  giving  the  fabric  a 
substantial  feel.  It  is  not  an  ideal  substance  to  use 
in  conjunction  with  starch,  however,  as  it  gives  rise 
to  dusty  mixings.  This  condition  is  brought  about 
by  the  action  of  the  Epsom  salts  on  the  starch  which 
it  tends  to  precipitate. 

SULPHATE  OF  SODA- 
GLAUBER'S  SALTS. 

This  substance  is  manufactured  on  a  large  scale 
by  adding  sulphuric  acid  to  common  salt  in  the  pro- 
cess of  preparing  soda  ash.  Sulphate  of  soda  is 
also  a  bye-product  in  the  preparation  of  nitric  acid 
from  sulphuric  acid  and  nitrate  of  soda.  The 
sulphate  of  soda  is  left  in  the  retort  as  a  residue, 
and  it  is  dissolved  out  with  hot  water.  The  acid  is 
afterwards  neutralised  with  soda  ash,  and  the  solu- 
tion concentrated,  cooled,  and  allowed  to  crystallize. 
These  crystals,  like  Epsom  salts,  contain  a  large 
percentage  of  water  of  crystallization,  more  than  half 
their  weight  being  water,  as  the  following  formula 
will  show  : — 

Na,S04,  10H,O 
142  180 

The  crystals  exist  as  four-sided  prisms.  They 
readily  give  up  their  water  on  exposure  to  the 
atmosphere,  finally  crumbling  to  a  powder. 

Sulphate  of  soda  should  not  be  used  in  con- 
junction with  chloride  of  calcium  in  sizing,  unless 

K 


1 62       The  Chemistry  and  Practice  of  Sizing. 


the  production  of  sulphate  of  calcium  be  desired. 
A  double  decomposition  takes  place  when  these 
two  substances  are  brought  together  in  solution,  and 
sulphate  of  calcium  is  precipitated.  If  the  chloride 
of  calcium  is  being  used  for  its  deliquescent  proper- 
ties they  would  be  lost,  and  the  substances  entirely 
changed  jn  their  character.  Chloride  of  magnesium 
should  always  be  used  as  a  deliquescent  when 
sulphate  of  soda  or  Epsom  salts  are  ingredients 
of  the  size. 

SULPHATE  OF  CALCIUM- 
SULPHATE  OF  LIME. 

This  substance  is  also  known  as  Gypsum,  the 
dehydrated  form  of  which  is  plaster  of  Paris. 

Sulphate  of  calcium  has  been  used  to  some 
extent  as  an  ingredient  of  size,  but  the  harsh 
feel  which  it  imparts  to  the  cloth  is  against  its 
general  use. 

A  mixture,  containing  precipitated  sulphate  of 
calcium,  cholride  of  calcium,  and  chloride  of  sodium, 
has  been  largely  sold  as  a  combination  for  producing 
good  weaving,  and  for  producing  a  "boardy  feel"  in 
the  cloth.  Mixtures  of  this  description  are  prepared 
by  mixing  together  strong  solutions  of  sulphate  of 
soda  (Glauber's  salts),  and  chloride  of  calcium.  On 
admixture  a  chemical  change  takes  place  ;  the  cal- 
cium is  precipitated  as  sulphate  of  calcium,  and 
chloride  of  sodium  is  produced  at  the  same  time.  As 


Sulphate  of  Calcium — Sulphate  of  Barium.    1 63 

a  rule  an  excess  of  chloride  of  calcium  is  used,  in 
which  case  the  whole  of  this  substance  is  not  entirely 
decomposed,  thus  leaving  a  portion  of  it  in  the  mixture 
as  chloride  of  calcium.  The  following  equation 
shows  the  chemical  change  which  takes  place  if  the 
substances  are  used  in  exact  proportions  : — 

Na2  S04  +  Ca  CL  =  2Na  CI  +  Ca  S04. 

Sulphate         Chloride         Chloride  Sulphate 
of  Soda.       of  Calcium.      of  Sodium,    of  Calcium. 

Any  merit  this  mixture  may  possess  for  pro- 
ducing good  weaving  is  due  to  the  excess  of 
chloride  of  calcium,  which  has  the  power  of  absorb- 
ing moisture.  It  is  therefore  a  round-about  way  of 
usinor  chloride  of  calcium  instead  of  adding  this 
substance  directly  to  the  size.  As  a  matter  of  fact  the 
use  of  such  a  mixture  is  only  making  the  size  more 
complicated  without  obtaining  any  improved  results. 

SULPHATE  OF  BARIUM. 
BARYTES.— MINERAL  WHITE. 

This  substance,  also  known  as  heavy  spar,  has 
been  used  as  a  weighting  ingredient  in  sizing  on 
account  of  its  high  specific  gravity.  It  is  not  a 
suitable  substance  to  use,  as  it  makes  the  yarns  very 
harsh,  thus  causing  the  healds  and  reeds  to  rapidly 
wear  out  by  friction.  Sulphate  of  barium  may  be 
employed  with  advantage  in  "finishing"  cotton 
goods,  because  there  is  not  the  same  liability  to 


164       The  Chemistry  and  Practice  of  Sizing. 

cause  damage  in  "finishing,"  as  there  is  where  it  is 
used  in  a  preparatory  process  like  sizing. 

French  Chalk. — Silicate  of  Magnesia. — 
Soapstone.— Steatite. — French  Chalk,  which  is 
known  in  commerce  under  all  the  above  names,  is 
used  occasionally  in  this  country  for  sizing  purposes 
instead  of  China  clay,  but  it  is  not  as  suitable  a 
weighting  material  as  the  latter.  French  chalk 
consists  mainly  of  silicate  of  magnesia,  and  it  is 
not  altogether  free  from  colour.  There  is  a  peculiar 
feature  about  this  substance  which  makes  it  less 
suitable  for  sizing  than  China  Clay,  apart  from  its 
colour,  and  that  is  the  difficulty  of  mixing  it  with 
the  other  ingredients  of  the  size.  French  chalk 
has  a  tendency  to  float. 

In  some  countries  French  chalk  is  largely  used 
for  weighting  in  place  of  China  clay,  especially  in 
India.  This  is  not  due  to  any  special  merit  in  the 
chalk  but  to  the  fact  that  they  have  it  on  the  spot, 
and  thus  save  the  heavy  cost  of  carriage  on  China 
clay  from  England.  This  applies  specially  to 
"up  country"  mills. 

Silicate  of  Soda — Soluble  Glass. — Chloride 
of  Barium. — These  substances  have  all  been  used 
for  sizing,  but  not  with  any  success. 


7 ^ allow. 


165 


Chapter  III. 

Ingredients  used  to  Soften  the  Size 
and  Yarn. 


FATS,  OILS,  AND  WAXES. 

'"T^ALLOW. — This  substance  consists  essentially 
JL  of  the  glycerides  of  stearic,  palmitic,  and 
oleic  acids.  When  distilled  with  superheated 
steam  tallow  yields  the  above-mentioned  acids  and 
glycerine.  Tallow  is  commercially  known  as  beef  or 
mutton  tallow.  In  England  the  two  are  generally 
mixed.  Mutton  tallow7  is  whiter  and  harder  than 
beef  tallow. 

Tallow  is  the  substance  which  is  most  subjected 
to  adulteration.  The  reason  for  this  is  not  far  to 
seek.  Tallow  is  the  most  expensive  ingredient  used 
in  sizing,  and  it  therefore  gives  the  biggest  margin 
of  profit  if  the  adulteration  can  be  carried  out  with- 
out exposure.     It  is  in  the  interests  of  all  honest 


1 66      The  Chemistry  and  Practice  of  Sizing. 

dealers  in  tallow,  therefore,  that  such  practices 
should  be  exposed,  as  a  dishonest  dealer  may  be 
able,  with  very  little  skill,  to  supply  so-called 
tallow  below  the  market  price  of  pure  tallow,  and 
make  a  very  considerable  profit  thereby.  It  is 
within  the  personal  knowledge  of  the  writer  that 
adulterated  tallow  is  being  sold  every  day  ;  the 
dealer  trusting  to  the  ignorance  of  the  buyer  to 
prevent  the  fact  becoming  known.  So  outrageously  is 
the  deception  carried  on  that  the  adulterated  tallow 
is  often  actually  sold  with  a  written  guarantee  of 
its  purity,  in  spite  of  the  absolute  knowledge  of  the 
sellers  to  the  contrary.  Their  safety  lies  in  the 
fact  that  sizers  and  manufacturers  very  rarely  have 
the  tallow  they  use  systematically  analysed,  and  so 
the  dishonest  dealer  escapes  detection.  It  is  useless 
to  expect  the  analyst  to  be  able  to  detect  adulterated 
tallow  after  it  has  been  mixed  with  the  size,  and  the 
size  put  on  the  yarn,  and  the  latter  woven  into  cloth, 
and  possibly  afterwards  bleached,  dyed,  or  printed. 
This  is  the  reason  why,  in  many  cases  of  damage  to 
cloth,  the  cause  cannot  be  definitely  ascertained^ 
although  it  may  be  more  than  suspected.  Manu- 
facturers pay  very  dearly  for  the  use  of  adulterated 
tallow.  In  the  first  place,  they  pay  for  something 
which  they  do  not  get,  and  in  the  second  place, 
they  are  continually  paying  for  damages  which  have 
been  developed  in  the  cloth  after  it  has  left  the 
weaving  shed. 


Substances  used  for  Adulterating  Tallow.  167 

The  substances  used  for  adulterating  tallow  may 
be  classified  as  follows  : — 

(1)  Fatty  substances  which  lower  the  commercial 
value  of  the  tallow. 

(2)  Substances  not  fat,  which  reduce  the  soften- 
ing effects  peculiar  to  fat. 

(3)  Substances  which  are  actually  injurious  to 
the  cloth. 

The  substances  mentioned  under  the  first  head- 
ing include  bone  and  marrow  fats,  cotton  seed  oil, 
cotton  seed  oil  stearine,  soap,  and  water.  They  are 
in  no  way  injurious  to  the  cloth,  and  with  the 
exception  of  soap  and  water,  have  softening 
properties  nearly  equal  to  pure  tallow. 

The  substances  mentioned  under  the  second 
heading  include  starch,  common  salt,  and,  in  a  lesser 
degree,  the  chlorides  of  calcium  and  magnesium. 
They  are  mixed  with  tallow  for  the  sole  object  of 
increasing  the  profits  of  the  dealer. 

The  chlorides  of  calcium  and  magnesium  may 
cause  damage  to  the  cloth  if  it  be  subjected  to  the 
singeing  process  previous  to  bleaching. 

The  substances  mentioned  under  the  third 
heading  include  paraffin  wax,  mineral  oil,  and 
recovered  Yorkshire  grease.  These  substances  may 
cause  serious  damage  if  used  for  sizing  yarns  in- 
tended for  cloth  which  has  to  be  bleached,  but  if 
the  cloth  is  intended  to  be  sold  and  used  in  the  grey 
state  and  not  bleached,  there  is  not  the  same  liability 


1 68      The  Chemistry  and  Practice  of  Sizing. 

to  cause  damage,  unless  the  mineral  oil  is  present  in 
sufficient  quantity  to  cause  the  cloth  to  show  oil 
stains  after  it  is  packed  and  pressed. 

Putting  the  question  of  damage  on  one  side 
altogether  it  is  necessary  that  the  practice  of  adulter- 
ating tallow  with  mineral  oils,  which  have  a  low 
vaporising  point,  should  be  strongly  condemned.  If 
tallow  of  this  description  be  boiled  for  any  length  of 
time  with  the  clay,  a  portion  of  the  mineral  oil  is 
converted  into  vapour,  and  this  is  carried  off  with 
the  steam  and  lost.  This  conversion  from  an  oil  to  a 
vapour  is  repeated  in  the  sow  box  of  the  tape  frame, 
and  manufacturers,  using  tallows  adulterated  in  this 
manner,  are  paying  for  a  substance  the  greater 
portion  of  which  is  driven  off  into  the  atmosphere 
instead  of  forming  a  portion  of  the  size  on  the  warp. 

The  objection  to  the  presence  of  paraffin  wax, 
mineral  oil,  and  recovered  Yorkshire  grease,  in  tallow 
used  in  sizing  goods  which  have  to  be  bleached,  and 
possibly  dyed  or  printed  afterwards,  is  as  follows:  — 
In  the  first  place  it  is  almost  impossible  to  remove 
paraffin  wax  or  mineral  oil  in  the  bleaching  opera- 
tions, and  therefore,  when  the  cloth  is  finished,  these 
substances  may  give  rise  to  stains  in  white  goods. 
In  the  second  place,  if  the  cloth  has  to  be 
printed  or  dyed,  the  dye  will  not  be  absorbed 
equally,  and  will  thus  give  rise  to  stains  of  a  serious 
nature.  This  matter  is  further  dealt  with  under 
paraffin    wax,   and    in    the    chapters    on  stains, 


Adulteration  of  Talloiv. 


169 


and  bleaching.  Recovered  Yorkshire  grease,  on 
account  of  the  amount  of  unsaponifiable  matter  it 
generally  contains,  is  not  easily  removed  during  the 
bleaching  operations,  and  it  may  give  rise  to  similar 
damage  to  that  produced  by  paraffin  wax  and 
mineral  oil. 

A  cross  case  0f  adulterated  tallow  came  under 
the  writers  notice  a  few  years  ago.  It  was  submitted 
for  analysis  with  the  questions  : — "  Is  this  pure 
tallow?  If  not,  what  proportion  of  tallow  is  there  in 
it?"  The  writer  reported  as  follows: — "The  sample 
is  not  pure  tallow.  It  contains  79*58  per  cent,  of 
tallow,  and  the  remainder  is  made  up  of  starch, 
common  salt,  chloride  of  magnesium,  and  water/' 
The  amount  of  the  sample  submitted  for  analysis 
was  not  sufficient  to  make  a  quantitative  analysis  of 
the  different  adulterants  found.  This  case  is  one 
of  the  most  flagrant  cases  of  adulteration  the  author 
has  met  with. 

More  recently  a  firm  of  manufacturers  decided 
to  have  their  sizing  arrangements  inspected  and 
reported  upon,  The  ingredients  used  for  making 
their  size  were  submitted  to  the  writer  for  analysis. 
The  tallow,  which  had  been  obtained  from  one  firm 
for  many  years  under  a  guarantee  of  purity,  was 
found  to  be  adulterated  with  Yorkshire  grease  and 
cotton  seed  oil  stearine.  The  result  of  the  writer's 
report  was  the  refunding  of  a  sum  of  Fifty  Pounds 
as  compensation  for  previous  deliveries,  a  sum  of 


ljo       The  Chemistry  and  Practice  of  Sizing. 


money  which  paid  for  the  writer's  services  many 
times  over. 

Examination  of  Commercial  Tallow. — From 
what  has  been  said  it  will  be  readily  seen  how 
necessary  it  is  that  all  samples  of  tallow  should  be 
carefully  and  regularly  analysed. 

The  following  is  a  list  of  the  more  important 
adulterants  which  have  been  found  in  tallow  by  the 
writer  : — 
Water. 

Mineral  Oil  and  Paraffin  Wax. 
Bone  and  Marrow  Fat. 
Cotton  Seed  Oil. 

"Stearine"  or  Stearic  Acid  from  Cotton  Seed  Oil. 

Recovered  Yorkshire  Grease. 

Starch. 

Chloride  of  Sodium — Common  Salt. 
The  Chlorides  of  Magnesium  and  Calcium. 
Other    mineral     matters,     such     as  Chalk, 
Barytes,  etc. 

The  following  tests  should  be  applied  before 
accepting  a  consignment  of  tallow  for  use  : — 

Vaporising  Point. — This  is  one  of  the  most 
important  tests  which  can  be  applied  to  tallow, 
giving  as  it  does  many  valuable  indications  of  the 
purity,  or  otherwise,  of  the  sample  under  exam- 
ination. The  test  is  conducted  as  follows  . — About 
two  ounces  of  the  tallow  should  be  melted  in  an 
evaporating  basin.      For  this  purpose  the  basin 


Vaporising  Point  of  Tallow, 


171 


should  be  placed  on  a  sand-bath,  the  latter  being 
heated  by  means  of  a  Bunsen's  flame.  As  soon  as 
the  tallow  melts  two  samples  should  be  collected  for 
the  purpose  of  determining  the  melting  point.  This 
is  done  by  dipping  the  ends  of  two  capillary  tubes, 
such  as  are  used  for  the  purpose  of  storing  vaccine 
lymph,  into  the  melted  fat.  These  should  be  laid 
on  one  side  for  twelve  hours  before  taking  the 
melting  point. 

A  thermometer,  registering  not  less  than  360° 
Fah.,  should  now  be  suspended  in  the  melted 
tallow,  in  such  a  way  that  the  bulb  is  entirely 
covered  with  the  fat.  This  thermometer  may  also 
be  used  as  a  stirring  rod.  The  heating  is  continued, 
and  the  first  point  to  be  noticed  is  the  presence  or 
absence  of  water.  If  the  tallow  melts  without  crack- 
ling, water  is  absent.  Sometimes  a  little  crackling 
occurs,  at  other  times  the  fat  will  spurt  out  of 
the  basin  if  not  carefully  stirred.  In  the  latter 
case  it  shows  the  presence  of  a  large  excess  of 
water,  and  the  amount  should  be  determined  as 
described  later. 

The  melted  fat  will  now  be  at  a  temperature 
about  that  of  boiling  water,  and  if  water  be  absent, 
the  point  at  which  the  tallow  gives  off  vapour  must 
be  carefully  noticed.  If  water  be  present  it  must  be 
removed  previous  to  determining  the  vaporising 
point.  This  is  done  by  heating  the  tallow  to  about 
212  degrees  Fah.,  and  constantly  stirring  until  no 


172       The  Chemistry  and  Practice  of  Sizing. 

more  globules  of  water  can  be  seen,  and  crackling 

ceases. 

Pure  tallow,  in  the  winter  months,  vaporises  at 
from  260°  Fah.  to  320°  Fah.,  according  to  the 
quality  of  the  fats  ;  the  higher  the  vaporising 
point,  the  better  the  tallow.  In  the  summer 
months  the  vaporising  point  is  considerably  lowered, 
due  probably  to  the  different  class  of  food  eaten 
by  the  animals,  but  it  should  never  vaporise 
below  240°  Fah. 

The  value  of  the  test  consists  in  the  certain 
detection  of  the  following  adulterants. 

(1)  Water,  which  is  shown  by  the  crackling 
produced. 

(2)  Mineral  Oil,  which  vaporises  at  a  temperature 
of  from  180°  to  230°  Fah.,  according  as  a  light  or 
heavy  oil  has  been  used  as  the  adulterant.  The 
vaporising  point  of  these  oils  is  generally  between 
180°  and  230°  Fah.  ;  i.e.,  sufficiently  low  to  give  an 
absolutely  certain  indication  of  their  presence. 
The  characteristic  smell  of  hot  mineral  oil  should 
be  looked  for  also. 

(3)  Starchy  Matter,  which  will  be  found  to 
aggregate  in  sticky  particles  at  the  bottom  of 
the  basin,  due  to  its  conversion  into  dextrin  by 
the  heat  applied. 

(4)  A  low  vaporising  point  also  indicates  one  or 
other  of  the  following  possible  adulterants  : — 
soap  (which    is    always    accompanied   by  water), 


Flash  Point  of  Tallow. 


173 


stearic  acid,  bone  fat,  marrow  fat,  and  Yorkshire 
grease. 

When  soap  is  present  a  certain  amount  of  froth- 
ing takes  place,  whilst  when  stearic  acid  is  present 
the  characteristic  smell  of  this  substance  is  rendered 
apparent.  Bone  and  marrow  fats  lower  the  vapor- 
ising point  and  melting  the  point  of  the  sample. 

It  will,  therefore,  be  seen  that  if  a  sample  of 
tallow  be  found  to  have  a  vaporising  point  of  over 
260°  Fah.,  and  does  not  show  the  presence  of 
water  or  starch,  and  there  is  no  smell  of  stearic  acid 
and  no  bone  fat  (the  test  for  which  is  described 
later),  it  may  be  safely  passed  as  pure  tallow,  and 
such  tests  as  the  "saponification  equivalent,"  and 
the  iodine  value  omitted. 

Flash  Point  Determination  (open  test). — The 
vaporising  point  test  may  be  carried  a  step 
further  and  the  flash  point  taken  as  follows  : — 
After  noting  the  vaporising  point  the  heating 
should  be  continued,  the  thermometer  being  pre- 
viously changed  for  one  registering  about  6oo° 
Fah.  A  blow-pipe  should  be  connected  to  a  gas 
supply  by  means  of  a  piece  of  rubber  tubing.  The 
flow  of  gas  is  regulated  so  as  to  get  a  flame  about 
the  size  of  a  pea.  The  test  is  made  by  bringing  this 
flame  almost,  but  not  quite,  in  contact  with  the 
surface  of  the  heated  tallow.  This  should  be  done 
at  intervals  of  a  few  seconds.  At  a  certain  temper- 
ature   the    vapour   will    inflame  ;    a    blue  flame 


174       The  Chemistry  and  Practice  of  Sizing, 

shooting"  across  the  surface  of  the  tallow.  This 
is  the  flash  point,  the  temperature  of  which  should 
be  noted.  Pure  tallow  should  not  flash  below 
500°  Fab.,  but  if  mineral  oil  be  present  it  will 
flash  at  the  same  temperature  at  which  the  oil 
would  flash  if  not  mixed  with  tallow.  The 
mineral  oils,  with  which  it  is  possible  to  adulterate 
tallow,  flash  at  temperatures  varying  from  340° 
to  380°  Fah. 

Melting  Point  of  Tallow. — This  most  valu- 
able test  should  always  be  applied  to  tallow.  The 
method  of  procedure  is  as  follows  : — One  of  the 
samples,  collected  in  the  capillary  tubes  as  described 
on  page  171,  is  fastened  to  a  thermometer  by  means 
of  an  elastic  band,  in  such  a  w7ay  that  the  column  of 
tallow  is  on  a  level  with  the  bulb  of  the  thermometer. 
The  thermometer  is  fixed  in  a  stand  and  immersed 
in  cold  water  contained  in  a  beaker.  This  beaker 
is  placed  inside  a  second  larger  beaker,  containing 
water,  in  such  a  way  that  the  inner  beaker  floats 
surrounded  by  water.  The  arrangement  of  beakers 
is  placed  on  a  tripod  stand  covered  with  copper 
gauze,  and  heat  applied  to  the  outer  beaker  by 
means  of  a  Bunsen's  flame.  The  heat  should  be 
applied  gradually,  the  temperature  not  increas- 
ing more  than  50  per  minute.  The  eye  should 
be  fixed  on  the  column  of  fat,  and  when  the 
temperature  is  about  105°,  the  Bunsen's  burner 
should    be    removed,    and    the    outer  jacket  of 


Melting  Point  of  Tallow.  175 

water,  which  is  hotter  than  the  water  in  the  inner 
beaker,  allowed  to  continue  the  heating.  By  this 
method  there  is  less  chance  of  error  in  taking  the 
melting  point  than  where  a  flame  is  applied  directly 
to  the  beaker  containing  the  thermometer.  At  the 
moment  of  melting,  the  column  of  tallow  will  suddenly 
rise  in  the  tube,  and  this  point  should  be  taken  as 
the  melting  point.  It  is  necessary  that  the  capilliary 
tube  should  be  long  enough  to  leave  the  upper  part 
well  out  of  the  water.  If  water  should  get  in  at  the 
top  of  the  tube,  it  would  prevent  the  tallow  rising 
easily,  and  the  melting  point  would  not  be  deter- 
mined so  accurately.  Working  in  this  way,  the 
authors  find  that  good  tallow  has  a  melting  point  of 
from  1 10  to  1 1 8°  Fah. 

A  tallow  having  a  high  melting  point  is  rarely 
an  adulterated  one.  Mineral  oil,  cotton  seed  oil, 
or  bone  fat,  more  especially  the  former,  reduces  the 
melting  point  considerably.  The  authors  always 
look  with  suspicion  upon  a  tallow  which  melts 
below  108°  Fah. 

After  taking  the  vaporising  point,  flash  point, 
and  melting  point,  the  tallow  may  be  further 
examined  as  follows  : — 

Detection  of  Bone  and  Marrow  Fats. — Bone 
and  marrow  fats  are  always  contaminated  with  a  very 
small  quantity  of  phosphate  of  calcium,  and,  unless 
this  substance  has  been  removed  by  the  producer 
previous  to  placing  it  on  the  market,  its  presence  in 


176        The  Chemistry  and  Practice  of  Sizijig. 


a  sample  of  tallow  is  a  certain  indication  of  the 
presence  of  bone  or  marrow  fat,  as  phosphate  of 
calcium  is  never  found  in  pure  beef  or  mutton 
tallow.  It  is  seldom  removed,  as  the  process  of 
purification  is  expensive,  and  it  would  bring  the 
price  of  the  adulterated  tallow  up  to  about  that  of 
pure  beef  or  mutton  tallow. 

The  following  method  of  procedure  should 
be  adopted  in  testing  for  bone  and  marrow 
fats  : — About  two  ounces  of  the  tallow  should  be 
boiled  in  water  containing  a  few  drops  of  strong 
hydrochloric  acid  The  whole  should  be  well 
stirred  and  then  allowed  to  cool.  When  the  cake 
of  fat  has  set  hard,  the  acid  solution  is  filtered  off, 
and  tested  for  the  presence  of  phosphoric  acid 
(phosphate  of  calcium)  as  follows  : — The  filtrate  is 
carefully  neutralised  by  means  of  solution  of 
ammonia.  An  excess  of  nitric  acid  is  then  added 
and  afterwards  an  excess  of  a  solution  of  molybdate 
of  ammonium.  A  yellow  precipitate  is  produced  if 
phosphates  be  present,  and  this  is  certain  evidence 
of  the  presence  of  bone  or  marrow  fat. 

The  presence  of  bone  and  marrow  fat  in  tallow 
can  be  recognised  by  the  expert,  even  if  the  phosphate 
of  calcium  has  been  removed.  Marrow  fat  gives  a 
characteristic  granular  appearance  to  the  tallow, 
whilst  bone  fat  gives  it  a  pasty  appearance. 

Test  for  Starch  and  Free  Acid. — Starch,  as 
previously  mentioned,  is  occasionally  found  as  an 


Starch  and  Mineral  Acids  in  Tallow.  177 

adulterant  in  tallow,  and  nearly  always  in  conjunction 
with  water.  Acids,  on  the  other  hand,  may  be  due 
to  the  presence  of  free  fatty  acids  (rancid  fats),  or 
to  sulphuric  or  hydrochloric  acids.  The  latter  acids 
are  sometimes  used  in  the  preparation  and  bleaching 
of  the  tallow.  The  method  to  be  adopted  for  testing 
for  these  various  substances  is  as  follows  : — About 
two  ounces  of  the  tallow  should  be  boiled  with  pure 
water  in  an  evaporating  basin.  The  mixture  should 
be  well  stirred  and  allowed  to  cool.  When  the  cake 
of  fat  has  set  hard,  the  liquid  is  poured  off,  filtered, 
and  divided  into  two  unequal  portions. 

(1)  Starch. — The  smaller  portion  is  tested  for 
starch  by  adding  a  few  drops  of  a  solution  of  iodine; 
a  blue  colour  is  produced  if  starch  be  present. 

(2)  Acids. — The  larger  portion  of  the  liquid  is 
tested  for  acids,  first,  by  means  of  blue  litmus  paper, 
which  will  show  the  presence  of  both  organic  and 
mineral  acids,  and  second,  by  means  of  methyl 
orange  paper,  which  will  show  whether  mineral  acid 
is  present  or  not.  In  no  case  should  tallow  be  used 
which  shows  any  reaction  with  methyl  orange,  as 
mineral  acids  have  a  most  disastrous  effect  on  size. 
If  acid  be  present  its  nature  should  be  determined, 
the  solution  being  divided  into  two  equal  portions 
for  this  purpose,  and  tested  as  follows  : — 

(a)  Hydrochloric  Acid. — A  few  drops  of  nitric 
acid  and  a  few  drops  of  a  solution  of  nitrate  of  silver 
should  be  added  to  one  portion  of  the  solution.  If 

L 


178       The  Chemistry  and  Practice  of  Sizing. 

hydrochloric  acid  be  present,  a  white  curdy  precipi- 
tate is  produced.  (N.B. — This  test  is  accurate  only 
if  other  chlorides,  such  as  magnesium  and  calcium 
chlorides,  and  common  salt,  be  absent). 

(b)  Sulphuric  Acid. — A  few  drops  of  hydro- 
chloric acid,  and  a  few  drops  of  a  solution  of  chloride 
of  barium  should  be  added  to  the  second  portion 
of  the  solution.  If  sulphuric  acid  be  present,  a 
heavy  white  precipitate  of  sulphate  of  barium  will 
be  produced. 

Tests  for  the  Chlorides  of  Magnesium  and 
Calcium, — These  substances  may  be  extracted  by 
boiling  a  sample  of  the  tallow  in  water,  as  described 
on  page  177.  After  cooling,  the  liquid  is  filtered 
from  the  fat,  and  tested  for  calcium  and  magnesium, 
as  follows  : — A  strong  solution  of  chloride  of  am- 
monium and  an  excess  of  a  solution  of  ammonia 
should  be  added,  and  afterwards  an  excess  of  solution 
of  oxalate  of  ammonium.  If  calcium  be  present,  a 
white  precipitate  will  be  formed.  The  mixture 
should  then  be  filtered,  and  a  solution  of  phosphate 
of  sodium  added.  If  magnesium  be  present,  a  white 
granular  precipitate  of  magnesium  ammonium 
phosphate  will  be  formed. 

The  presence  of  the  various  chlorides  may  be 
determined  by  testing  a  portion  of  the  liquid  with 
nitrate  of  silver  and  nitric  acid.  In  the  absence  of 
calcium  and  magnesium,  the  production  of  a  large 
amount  of  the  curdy  white  precipitate  of  chloride  of 


Determination  of  Water  in  Tallow.  179 


silver  would  indicate  the  presence  of  common  salt. 
This  should  be  confirmed  as  follows  : — 

Test  for  Chloride  of  Sodium  (Common  Salt). 
A  portion  of  the  solution,  obtained  by  boiling  the 
tallow  in  pure  water,  should  be  evaporated  to  dry- 
ness on  the  water  bath.  The  residue  is  dissolved 
in  as  small  a  quantity  of  water  as  possible,  filtered, 
and  the  solution  poured  into  a  long  narrow  test  tube. 
To  this  should  be  added  twice  its  bulk  of  strong" 
hydrochloric  acid.  A  white  granular  precipitate 
will  be  formed  if  common  salt  be  present.  Pre- 
cipitation will  take  place,  by  this  treatment,  in  the 
presence  of  the  chlorides  of  magnesium  and  calcium. 

Mineral  Matters — (Chalk,  Barytes,  etc.) — 
These  substances  may  be  detected  as  follows : — 5  or 
10  grammes  of  tallow  should  be  dissolved  in 
petroleum  spirit,  filtered,  and  the  residue  examined. 
A  portion  treated  with  hydrochloric  acid  will  effer- 
vesce if  chalk  be  present,  whilst  barytes  will  remain 
as  an  insoluble  residue. 

Determination  of  the  Percentage  of  Water 
in  Tallow. — If  water  has  been  detected  in  the 
preliminary  examination  of  the  tallow  the  amount 
should  be  determined  quantitatively  as  follows  : 

About  five  grammes  of  tallow  should  be  carefully 
weighed  in  a  tared  evaporating  basin,  along  with  a 
glass  rod,  the  weight  of  which  has  been  taken. 
The  basin  and  contents  are  then  placed  on  the 
sand  bath  and  heat  applied,  care  being  taken  that 


1 80       The  Chemistry  and  Practice  of  Sizing. 

the  temperature  of  the  tallow  does  not  rise  much 
above  212°  Fah. 

When  the  tallow  melts,  globules  of  water  will 
be  seen  at  the  bottom  of  the  basin,  and  as  the  tem- 
perature increases,  these  will  break  up  and  pass 
away  in  the  form  of  steam.  The  tallow  should  be 
constantly  stirred  until  the  whole  of  the  water  has 
evaporated,  a  point  easily  seen  if  the  tallow  be 
allowed  to  remain  undisturbed  for  a  few  seconds 
whilst  the  heating  is  continued.  If  the  water  has 
disappeared  the  tallow  will  be  quite  clear,  and  no 
further  steam  bubbles  will  rise  to  the  surface.  The 
basin  and  contents,  with  the  glass  rod,  are  allowed 
to  cool,  then  weighed,  and  the  loss  in  weight,  which 
will  be  the  water,  is  calculated  to  a  percentage  of 
the  tallow  taken. 

This  test  will  not  be  accurate  should  there  be 
present  a  low  vaporising  mineral  oil,  but  even  in 
this  case  it  will  be  sufficiently  accurate  for  all 
practical  purposes,  as  it  still  represents  loss  at  a 
temperature  of  21 2°  Fah. 

Test  for  Recovered  Yorkshire  Grease. — 
This  substance  is  very  frequently  used  for  the 
purpose  of  adulterating  tallow,  and  it  is  a  most 
objectionable  ingredient.  Tallow  mixed  with  this 
" recovered"  grease  is  generally  of  a  very  bad 
colour,  and  it  often  contains  a  large  percentage  of 
unsaponifiable  matter.  It  also  frequently  contains 
mineral  oil,  due  to  the  use  of  adulterated  oil  for 


Yorkshire  Grease  and  Cotton  Seed  Oil  Stearine,  1 8 1 

scouring  purposes,  and  on  this  account  may  be 
detected  in  the  preliminary  examination  by  means 
of  the  vaporising  test.  The  fatty  acids  obtained 
from  tallow,  adulterated  with  Yorkshire  grease,  are 
dark  coloured,  sometimes  of  a  deep  orange,  and 
frequently  black.  Yorkshire  grease  contains  a  large 
percentage  of  free  fatty  acids,  and  its  presence  in 
tallow  may  be  detected  by  estimating  the  quantity 
of  the  acids  contained  therein,  as  described  on  page 
1 86  et  seq.  Samples  of  so  called  pure  tallow,  sold 
at  pure  tallow  prices,  are  frequently  submitted  to 
the  writer,  and  on  analysis  are  found  to  contain 
60  to  70  per  cent,  of  free  fatty  acids. 

It  is  interesting  to  know  how  the  olive  oil  used 
in  wool  scouring  comes  to  be  adulterated  with 
mineral  oil.  Buyers  request  to  be  supplied  with  a 
60  per  cent,  saponifiable  oil.  Pure  olive  oil  should 
be  practically  entirely  saponifiable,  and  in  order  to 
produce  a  60  per  cent,  saponifiable  oil,  the  dealer 
must  use  mineral  oil.  Why  60  per  cent,  should  be 
stated  no  one  knows.  Possiblv  this  accounts  for 
the  bad  colours  complained  of  in  the  Bradford 
trade. 

Test  for  Cotton  Seed  Oil  Stearine: — Cotton 
seed  oil  stearine  is  extensively  used  for  the  purpose 
of  adulterating  tallow.  It  is  lower  in  price  than 
pure  beef  or  mutton  tallow  but  higher  in  price  than 
"  recovered  Yorkshire  Stearine."  Its  presence 
may  be  ascertained  and  the  amount  approximately 


1 82       The  Chemistry  and  Practice  of  Sizing. 


determined  by  estimating  the  quantity  of  free  fatty 
acids,  as  described  on  page  1 86  et  seq.  A  high 
percentage  of  free  fatty  acids,  together  with  the 
absence  of  unsaponifiable  matter  (always  found  when 
"Yorkshire  Stearine"  is  present),  is  a  fairly  certain 
indication  of  the  r.esence  of  cotton  seed  oil  stearine. 

The  principal  objection  to  cotton  seed  oil  stearine 
in  tallow  is  that  it  is  an  adulterant.  Another 
objection  is  that  it  is  likely  to  produce  a  rancid  smell 
in  the  cloth  after  it  has  been  stored  for  some  time. 

Determination  of  the  Percentage  of  Mineral 
Oil  and  Wax  in  Tallow. — The  percentage  of 
mineral  oil  or  wax  in  a  sample  of  tallow  may  be 
determined  as  follows: — About  5  grammes  of  tallow 
should  be  carefully  weighed  and  saponified  with  an 
alcoholic  solution  of  caustic  potash. 

The  potash  solution  is  made  by  dissolving  80 
grammes  of  the  alkali  in  one  litre  of  methylated 
spirit,  the  spirit  having  previously  been  de-hydrated 
by  the  following  treatment : — 

Methylated  spirit  is  digested  with  a  large  excess 
of  dried  carbonate  of  potassium  for  some  time.  The 
spirit  is  then  decanted  into  a  suitable  flask,  a  little 
caustic  potash  added,  and  allowed  to  stand  for  a  day 
or  two.  The  flask  is  then  connected  with  a  Liebigs 
condenser  and  a  receiver,  and  the  spirit  distilled  off. 
This  de-hydrated  spirit  should  be  stored  in  well- 
stoppered  bottles,  and  may  be  used  for  making  the 
standard    potash    solution,  which    is    used  when 


Mineral  Oil  and  Wax  in  Tallow.  183 


determining  the  saponification  equivalent  of  tallow 
and  of  other  fats  and  oils. 

The  operation  of  saponification  may  be  conducted 
in  a  porcelain  basin  on  the  water  bath.  About 
30  c.c.  of  the  potash  solution  is  added  to  the  tallow 
and  kept  constantly  stirred  with  a  glass  rod,  until 
the  alcohol  is  nearly  driven  off  and  the  residual 
liquid  froths  strongly.  If  incomplete  saponification 
be  suspected,  10  or  15  c.c.  of  potash  solution  is  again 
added  and  the  evaporation  repeated.  The  soap 
produced  should  be  diluted  with  warm  water,  and 
transferred  to  a  stoppered  pear  -  shaped  glass 
separator  of  about  200  to  250  c.c.  capacity,  to  which 
is  fitted  a  tap.  The  basin  should  be  rinsed  out 
with  more  water,  to  ensure  the  complete  removal  of 
the  soap,  and  the  washings  added  to  the  contents  of 
the  separator.  If  the  fat  or  oil  be  free  from  mineral 
oil  or  wax,  the  solution  will  be  perfectly  clear,  but 
if  mineral  oil  be  present  globules  of  it  will  be  seen 
in  the  solution.  About  50  c.c,  of  ether  should  next 
be  added,  and  the  mixture  thoroughly  shaken  and 
allowed  to  stand.  The  liquid  will  readily  separate 
into  two  distinct  layers,  the  ether,  containing  the 
mineral  oil,  floating  on  the  top  of  the  soap  solution. 
The  soap  solution  is  carefully  run  off  into  another 
separator  and  about  10  c.c.  of  water  added  to  the 
ether  in  the  first  one.  This  is  again  well  shaken 
and  the  washings  are  run  off  into  a  separator 
containing  the  soap. 


1 84      The  Chemistry  and  Practice  of  Sizing. 

The  solution  of  mineral  oil  in  ether  is  poured 
through  the  mouth  of  the  separator  into  a  tared 
evaporating  basin,  and  the  soap  solution  is  treated 
with  more  ether,  separation  takes  place  as  before, 
the  soap  solution  is  again  run  off  into  a  separating 
funnel,  and  the  ether  solution  washed  with  water. 
The  wash  water  is  run  into  the  soap  solution,  and 
the  ether  poured  into  the  evaporating  basin  or  flask 
containing  the  product  of  the  first  separation.  The 
process  is  repeated  a  third  time  when  all  mineral 
oil  will  be  removed  from  the  soap. 

The  ether  solution  is  evaporated  on  the  water 
bath,  or,  better  and  safer,  and  with  less  waste,  the 
evaporation  is  conducted  in  a  flask,  to  which  is  fitted 
a  condensor.  When  the  ether  has  been  distilled  off, 
as  far  as  possible,  a  current  of  air  is  blown  through 
the  flask  until  the  smell  of  ether  disappears. 
The  flask  is  weighed  and  the  tare  deducted.  The 
weight  of  mineral  oil  found  is  calculated  to  a 
percentage  of  the  tallow  originally  employed. 

Determination  of  the  Combined  Fatty  Acids 
in  Tallow. — The  soap  solution  from  the  previous 
test  should  be  placed  in  a  separating  funnel  and  an 
excess  of  sulphuric  acid  added.  After  shaking  up, 
a  quantity  of  ether  is  poured  into  the  separator  and 
well  agitated.  The  mixture  is  allowed  to  settle  until 
the  separation  of  the  ethereal  layer  is  complete. 
The  aqueous  solution  is  then  carefully  run  off  A 
few  drops  of  chloride  of  barium  solution,  and  a 


Combined  Fatty  Acids  in  Tallow.  185 


quantity  of  water,  should  now  be  added  to  the 
ethereal  solution  in  order  to  precipitate,  as  barium 
sulphate,  any  excess  of  sulphuric  acid.  This  may 
be  removed  afterwards  along  with  the  water.  The 
ethereal  solution  of  fatty  acids  should  be  washed  two 
or  three  times  with  water,  and  finally  transferred  to 
a  tared  basin  or  flask,  and  the  ether  removed  by 
evaporation,  with  the  precautions  previously 
described.  The  weight  of  the  residue  having  been 
found,  it  is  calculated  to  a  percentage  of  the  tallow 
originally  taken. 

The  following  method  is  a  simpler  one  for  deter- 
mining the  combined  fatty  acids  in  fats  and 
oils,  provided  mineral  oil  or  paraffin  wax  be 
absent  : — 

An  evaporating  basin  and  a  glass  rod  should  be 
carefully  weighed.  About  5  grammes  of  the  fat  or 
oil  is  then  placed  in  the  basin  and  the  whole  weighed 
again  ;  the  difference  in  weight  gives  the  amount  of 
fat  taken.  This  is  then  converted  into  soap  with 
alcoholic  potash  as  previously  described.  The  soap 
is  dissolved  in  hot  water,  and  an  excess  of  hydro- 
chloric acid  added.  This  decomposes  the  soap, 
combining  with  the  potash  to  form  chloride  of 
potassium,  whilst  the  fatty  acids  are  liberated. 
These  are  allowed  to  cool,  and  when  thoroughly 
cold  the  cake  of  fat  should  be  lifted  out,  by  means 
of  the  glass  rod,  and  the  hydrochloric  acid  and  water 
remaining,  poured  away.    Sometimes,  as  in  soft  soap, 


1 86      The  Chemistry  and  Practice  of  Sizing. 

and  also  in  the  case  of  hard  soaps  made  from  oils,  the 
fat  does  not  set  hard  on  cooling.  In  such  cases  it  will 
be  necessary  to  add  a  weighed  quantity  of  bees  wax  ; 
about  2  or  3  grammes,  after  the  fatty  acids  have 
been  liberated,  in  order  to  cause  them  to  solidify  on 
cooling.  After  cooling,  the  whole  is  re-melted  in 
contact  with  water,  and  well  stirred,  in  order  to  wash 
out  all  traces  of  hydrochloric  acid.  The  mixture  is 
again  allowed  to  cool,  the  fat  and  wax  removed  as 
before,  and  laid  upon  a  sheet  of  clean  blotting  paper, 
which  absorbs  the  moisture.  The  water  in  the  basin 
is  then  poured  out,  care  being  taken  that  no  particle 
of  fatty  acids  is  lost.  The  bottom  and  sides  of  the 
basin  are  then  carefully  dried  by  means  of  blotting 
paper.  The  cake  of  fat  is  replaced  and  carefully 
heated.  If  any  water  remain,  crackling  will  com- 
mence, in  which  case  the  melted  fat  should  be 
rapidly  stirred  to  prevent  spurting,  until  the  water  is 
evaporated.  The  whole  should  be  allowed  to  cool, 
and  then  carefully  weighed. 

The  weight  of  the  basin  and  rod,  and  the  weight 
of  the  bees  wax  (if  this  latter  substance  has  been 
added)  is  deducted  from  the  total  weight,  the 
remainder  being  the  weight  of  fatty  acids  originally 
combined  in  the  tallow.  This  weight  should  be 
calculated  to  a  percentage. 

Determination  of  Free  Fatty  Acids  in 
Tallow. — This  test  is  an  important  one  because 
tallow  frequently  contains  free  fatty  acids,  due  to 


Determination  of  Free  Fatty  Acids  in  Tallow,  187 

the  practices  of  adulterating  it  with  "  recovered 
Yorkshire  stearine"  and  cotton  seed  oil  stearine. 

The  proportion  of  fatty  acids  may  be  quantita- 
tively determined  by  dissolving  a  weighed  quantity 
of  the  sample  in  alcohol  (de-hydrated  methylated 
spirit)  and  titrating  with  alcoholic  soda  solution 
of  known  strength,  using  phenol-phthalein  as 
indicator.  The  following  are  the  details  of  the 
method,  which  was  first  proposed  by  Hausamaun  : — 
Methylated  spirit  is  purified  by  re-distillation  with 
a  little  caustic  soda.  A  small  quantity  of  phenol- 
phthalein  is  added,  and  then  dilute  caustic  soda, 
drop  by  drop,  until  the  liquid  retains  a  faint 
pink  colour  after  shaking.  This  preliminary 
treatment  of  the  alcohol  is  intended  to  secure 
the  absence  of  any  free  acid.  An  accurately 
weighed  quantity  of  the  sample,  about  5  grammes 
of  a  fatty  acid  or  50  grammes  of  an  ordinary  oil  or 
fat,  is  then  introduced  into  a  flask  furnished  with  a 
glass  stopper.  From  50  to  100  c.c.  of  the  neutralised 
spirit  is  then  added,  and  raised  to  the  boiling  point 
by  immersing  the  bottle  in  hot  water.  The  contents 
are  thoroughly  shaken,  in  order  to  effect  the  complete 
solution  of  the  fatty  acids  present.  If  the  sample 
be  entirely  free  from  fatty  acids,  the  pink  colour  will 
remain,  otherwise  it  will  have  disappeared.  In  the 
latter  case  a  decinormal  solution  of  caustic  soda 
(  =  •004  NaHO  per  cubic  centimetre)  is  gradually 
added  from  a  burette  until  the  pink  colour  is  just 


1 88      The  Chemistry  and  Practice  of  Sizing, 

restored.  Each  c.c.  of  decinormal  soda  ='0282  oleic 
acid  or  '0284  of  stearic  acid. 

Determination  of  the  Saponification  Equiva- 
lent of  Tallow. — The  following  method,  described 
by  Koettstorfer,  may  be  used: — 3  or  4  grammes  of 
the  tallow  should  be  carefully  weighed  in  a  small 
glass  flask  of  about  four  ounces  capacity.  30  c,c.  of 
seminormal  solution  of  caustic  potash  in  alcohol  is 
added  from  a  fine  burette.  The  flask  is  fitted  with 
a  cork  through  which  is  passed  a  long  glass  tube. 
The  flask  and  contents  are  heated  on  the  water 
bath  for  half-an-hour,  or  until  the  saponification  is 
judged  to  be  complete.  The  contents  of  the  flask 
should  be  continually  rotated.  A  blank  experiment 
is  conducted  at  the  same  time  by  heating  30  c.c.  of 
the  same  alcoholic  potash  in  a  similar  flask  fitted 
with  a  cork  and  long  tube.  1  c.c.  of  an  alcoholic 
solution  of  phenol-phthalein  is  then  added  to  each 
flask,  and  both  titrated  with  seminormal  hydrochloric 
acid.  The  difference  in  the  number  of  cubic 
centimeters  of  acid  employed  in  the  two  testings 
represents  the  number  of  cubic  centimeters  of 
alkali  combined  with  the  fat.  Each  c.c.  of  semi- 
normal  acid  =0*01825  of  H CI  and  represents  0  02805 
of  KHO.  From  the  data  arrived  at,  the  percentage 
of  caustic  potash  required  to  saponify  the  fat  can 
be  readily  calculated. 

The  saponification  equivalent  is  found  by  divid- 
ing the  weight  of  the  sample  employed,  expressed 


Specific  Gravity  of  Tallow.  189 


in  milligrammes,  by  the  number  of  c.c.  of  normal 
acid  (not  seminormal)  corresponding  to  the  alkali 
neutralised  by  the  oil  or  fat.  If  the  percentage  of 
potash  required  be  known,  the  saponification 
equivalent  can  be  found  by  dividing  this  percent- 
age into  5610.  The  amount  of  caustic  potash 
required  to  saponify  tallow  is  from  19*3  per  cent,  to 
19*8  per  cent.  The  saponification  equivalent  is 
from  283  to  290.  If  a  tallow  be  saponified  with  half 
the  above  percentage  of  caustic  potash,  it  would 
probably  mean  that  50  per  cent,  of  unsaponifiable 
hydro-carbon  (mineral)  oil  was  present. 

Specific  Gravity  of  Tallow. — Important 
evidence  of  the  purity  of  a  sample  of  tallow 
may  be  obtained  by  taking  the  specific  gravity. 
The  following  is  the  best  method  of  procedure: — A 
specific  gravity  bottle,  with  a  well-fitting  perforated 
stopper,  is  charged  with  the  melted  fat  in  the  ordinary 
way.  In  the  meantime  a  large  glass  beaker,  or 
other  suitable  vessel,  is  filled  with  water  and  set  to 
boil  over  a  Bunsen's  flame. 

When  the  water  begins  to  boil,  the  charged 
specific  gravity  bottle  is  immersed  in  the  water  by 
means  of  a  pair  of  tongs,  and  the  boiling  briskly 
continued.  The  heated  fat  expands,  and,  by  passing 
through  the  stopper,  prevents  any  water  making  its 
way  into  the  bottle.  The  tallow  should  be  boiled 
for  just  twenty  minutes.  The  bottle  is  then  taken 
out,  rapidly  wiped  dry,  cooled,  and  weighed.  The 


1 90       The  Chemistry  and  Practice  oj  Sizing. 

weight,  less  the  tare  of  the  bottle,  gives  the  weight 
of  fat  it  holds  at  the  boiling  point  of  water.  This, 
divided  by  the  weight  of  water  held  by  the 
bottle  at  6o°  Fah.,  gives  the  specific  gravity. 
Tallow  has  a  specific  gravity  of  '857  to  '862  taken 
under  these  conditions.  In  the  case  of  oils  the 
specific  gravity  is  taken  in  the  ordinary  way  at 
6o°  Fah. 

The  tests  described  under  tallow  may  be  applied 
to  the  other  oils,  fats  and  waxes,  used  in  sizing,  and 
the  results  compared  with  the  table  at  the  end  of 
this  chapter. 

TALLOW  SUBSTITUTES. 

Whenever  the  price  of  tallow  advances,  large 
numbers  of  cheaper  substitutes  are  put  upon  the 
market  for  sizing  purposes.  Some  are  sold  as 
substitutes,  whilst  others  are  used  for  the  purpose 
of  adulterating  tallow. 

Innumerable  attempts  have  also  been  made  to 
bring  out  some  substitute  for  tallow  which  would 
give  similar  results  at  a  reduced  cost.  So  far  they 
have  all  signally  failed  in  achieving  this  object,  and 
manufacturers  would  be  acting  in  their  own  interests 
if  they  left  these  preparations  severely  alone. 

No  substance  has  yet  been  placed  upon  the 
market  which  will  give  as  good  results  as  tallow  for 
any  class  of  sizing  where  chloride  of  magnesium  or 


Analysis  of  Tallow  Substitutes. 


191 


chloride  of  zinc  are  constituents  of  the  size  mixing. 
It  is  impossible  to  obtain  anything  like  the  softening 
effects  by  substituting  soap  or  tallow  substitutes  of 
any  description.  In  the  case  of  good  honest  soap 
the  sizer  knows,  at  any  rate,  what  he  is  purchasing, 
but  in  the  case  of  tallow  substitutes  he  is  generally 
paying  a  high  price  for  absolute  rubbish. 

Tallow  substitutes  are  generally  made  by  boiling 
together  tallow,  caustic  soda,  and  water.  Some- 
times a  little  gum  tragacanth,  starch,  and  glycerine, 
is  added  to  the  mixture.  As  a  rule,  these  various 
tallow  substitutes  contain  a  little  free  alkali,  some- 
times they  contain  free  fat,  and  not  uncommonly 
they  contain  both  free  alkali  and  free  fat.  This 
latter  condition  is  owing  to  the  fact  that  the  mixture 
has  not  been  properly  boiled.  If  fatty  matter  be 
mixed  with  soap  and  water,  it  is  possible  to  obtain 
a  substance  which  is  fairly  hard,  and  shows  little  or 
no  evidence  of  the  presence  of  an  excessive  quantity 
of  water. 


No.  1 

per  cent. 

No.  2 
per  cent. 

No.  3 
per  cent. 

No.  4 
per  cent. 

Actual  Dry  Soap  

Free  Caustic  Soda   

Water  

Glycerine    ... 

Free  Fatty  Matter  

Combined  Fatty  Acid... 

26-58 
0*26 
73-16 

9'3° 
0*25 

9045 

22'IO 

°'5° 

4-90 

5-78 
074 

45*44 
48*04 

lOO'OO 

IOO'OO 

IOO'OO 

ICO'OO 

23-40 

686 

i8-3 

192       The  Chemistry  and  Practice  of  Sizing. 


From  the  preceding  figures  it  will  be  seen  that 
only  one  of  these  so-called  tallow  substitutes  contained 
free  fat  at  all.  They  are  simply  badly  prepared  low 
class  soaps,  in  which  water  is  the  predominating 
ingredient.  For  heavy  or  medium  sizing  they  are 
almost  useless  ingredients,  They  might  be  useful 
in  pure  sizing,  if  used  in  conjunction  with  tallow, 
but  it  would  be  far  better  and  cheaper  for  the 
manufacturer  to  purchase  a  good  hard  soap,  or 
good  soft  soap,  and  dilute  with  water  himself.  The 
samples  marked  No.  1  and  No.  2  were  supposed  to 
be  the  same  substances,  but  the  manufacturer, 
becoming  suspicious  that  the  quality  was  not  being 
kept  up,  sent  the  writer  samples  from  different 
consignments.  It  was  found  that  No.  2  contained 
only  one-third  of  the  amount  of  active  ingredient 
contained  in  No.  1. 

If  manufacturers  were  desirous  of  usino-  such 
substances  as  either  of  the  stronger  tallow  sub- 
stitutes, they  could  be  easily  prepared  by  boiling 
up  a  good  hard  soap  with  water.  The  following 
proportions  would  be  suitable: — 

White  hard  soap    30  lbs. 

Water    *]\  gallons. 

To  this  mixture  about  a  quarter-of-a-pound  of 
powdered  caustic  soda  should  be  added.  The 
addition  of  about  5  per  cent,  of  glycerine  would 
improve  the  weaving. 


Bone  and  Marrow  Fats, 


193 


The  value  of  most  of  the  tallow  substitutes 
depends  upon  the  amount  of  soap  contained  therein, 
and  as  a  good  hard  soap  contains  from  60  to  70 
per  cent,  of  fatty  acids  in  combination,  as  against 
6*8  to  23*4  per  cent,  found  in  many  tallow  substitutes, 
as  shown  by  the  above  analyses,  it  would  be  to  a 
manufacturers  or  sizer's  advantage  to  make  his  own 
tallow  substitute,  especially  as  by  doing  so  he 
is  not  tied  to  one  individual  for  his  ingredients,  nor 
is  he  dependent  upon  anyone  for  his  results. 

Another  class  of  tallow  substitute  is  made  by 
emulsifying  mineral  oil.  This  is  manufactured  as 
follows: — The  moisture  is  removed  from  soap  as 
nearly  as  possible  by  drying.  A  known  weight  of 
mineral  oil,  '885  specific  gravity,  is  heated  to  about 
180°  Fah.,  and  to  every  56  lbs.  of  oil  about  half-a- 
pound  of  the  dried  soap  is  added,  and  the  heating 
continued  until  the  soap  is  dissolved  in  it.  The 
mixture  is  then  allowed  to  cool,  the  product  being 
a  grease  of  great  body.  Sometimes  paraffin  wax  is 
added  to  give  extra  solidity.  There  are  the  same 
objections  to  the  use  of  this  form  of  tallow  substitute 
as  there  is  to  the  use  of  mineral  oil. 

BONE  AND  MARROW  FATS. 

These  substances  are  obtained  by  boiling  the 
bones  of  various  animals  in  water  under  pressure,  or 
by  the  action  of  solvents,  such  as  benzene,  etc. 

M 


1 94      The  Chemistry  and  Practice  of  Sizing, 


BONE  FAT— Bone  Grease. 

This  substance  is  generally  dark  in  colour,  and 
unpleasant  in  smell;  this  latter  characteristic  being 
due  to  its  contact  with  decomposed  animal  matter, 
such  as  blood.  Bone  fat  is  softer  than  tallow, 
melting  from  about  ioo°  to  104°  Fah.  It  also 
has  a  lower  vaporising  point.  Except  for  these 
points,  and  for  the  fact  that  it  contains  phosphate 
of  lime  (phosphate  of  calcium),  it  could  not  be 
distinguished  chemically  from  tallow.  Occasionally 
bone  fat  is  purified  by  treating  it  with  hydrochloric 
acid.  This  dissolves  the  phosphate  of  calcium,  which 
may  then  be  removed  by  washing  with  water. 

MARROW  FAT. 

Marrow  fat  is  generally  of  a  creamy  tint,  and 
has  a  peculiar  granular  appearance  when  cut.  The 
same  characteristic  appearance  is  seen  in  home- 
rendered  dripping.  Even  after  re-melting  the 
granular  appearance  shows  on  cooling.  Round  each 
granule  there  appears  to  be  a  more  oily  fat.  Marrow 
fat  melts  at  a  lower  temperature  than  bone  fat.  It 
contains  phosphate  of  calcium,  the  test  for  which 
has  been  described  under  tallow.  It  may  be  used 
in  sizing  for  the  same  purpose  as  bone  fat.  Marrow 
fat  is  generally  of  a  good  colour,  and  it  is  free  from 
objectionable  smell.  For  this  reason,  it  may  be  used 
as  the  "softening  agent"  in  any  class  of  sizing. 


Cocoa-nut  and  Olive  Oil.  195 


COCOA-NUT  OIL. 

Cocoa-nut  oil  is  occasionally  used  as  a  "softener" 
in  sizing.  It  is  a  white  fat,  having  the  consistency 
of  lard  or  butter,  and  the  characteristic  smell  of 
cocoa-nut.  The  melting  point  is  low,  and  varies 
considerably,  ranging  from  68°  to  82°  Fah. 

Cocoa-nut  oil  combines  with  alkalies,  producing 
soaps.  These  soaps  are  sometimes  known  as  marine 
soaps,  due  to  the  fact  that  they  can  be  used  with 
salt  water.  Unlike  the  solutions  of  soaps  made  from 
other  fats  and  oils,  cocoa-nut  oil  soap  is  not  readily 
precipitated  by  means  of  salt  solution.  Cocoa-nut 
oil  soap  may  contain  a  very  much  larger  percentage 
of  water  than  other  soaps  and  yet  remain  hard. 
Cocoa-nut  oil  is  largely  used  in  sizing  in  conjunction 
with  Epsom  salts.  It  has  the  property  of  mixing 
more  readily  with  this  substance  than  any  other  oil 
or  fat. 

Sizing  pastes,  which  consist  essentially  of  cocoa- 
nut  oil  soap  and  water  in  which  an  excess  of  the 
oil  is  afterwards  dissolved,  are  largely  sold. 

OLIVE  OIL. 

This  oil  is  used  in  sizing,  but  only  to  a  limited 
extent.  It  is  frequently  adulterated,  the  chief 
substances  used  for  this  purpose  being  mineral  oil, 
cotton  seed  oil,  poppy  oil,  sesame  oil,  and  rape  oil. 
Mineral  oil  may  be  detected   generally   by  the 


196       The  Chemistry  and  Practice  of  Sizing. 

fluorescent  appearance  of  the  sample,  unless  a 
bloomless  mineral  oil  has  been  used.  In  any  case, 
its  presence  may  be  detected  by  taking  the 
vaporising  point.  The  other  adulterants  are  less 
easily  detected,  and  should  be  left  to  the  trained 
analyst. 

PALM  OIL. 
This  oil,  when  bleached,  is  used  extensively  in 
sizing.  It  varies  considerably  in  consistency,  some- 
times being  as  soft  as  lard,  at  other  times  as  hard 
as  tallow.  The  melting  point  varies  to  the  same 
extent  as  the  consistency.  Unbleached  palm  oil 
varies  in  colour  from  a  brownish  yellow  to  a  deep 
orange,  and  has  a  characteristic,  but  not  unpleasant 
smell  The  oil  is  frequently  adulterated  with  water, 
the  amount  of  which  may  be  determined  by  the 
method  described  on  page  179. 

CASTOR  OIL. 
Castor  oil  is  very  rarely  used  in  sizing,  although 
it  is  largely  used  in  the  form  of  soluble  oil  and 
oleine  oil    by  dyers  and  finishers.       Castor  oil 
possesses  softening  properties  to  a  marked  degree. 

TURKEY  RED  OIL. 
Alizarine  Oil. — "Oleine"  Oil. 
This  substance  is  obtained  by  treating  castor  oil 
with  strong  sulphuric  acid.     It  is  occasionally  used 


uOleine  Oil" — Turkey  Red  Oil. 


197 


as  a  softener  in  sizing,  but  more  often  in  the 
finishing  of  cotton  goods. 

The  following  is  the  mode  of  procedure  adopted 
in  the  preparation  of  "  oleine  "  oil  :— The  castor 
oil  and  sulphuric  acid  are  mixed  together  in  lead- 
lined  tanks,  in  which  a  stirring  arrangement  is  fitted. 
The  tanks  are  generally  jacketed  in  order  to 
allow  water  to  be  circulated  for  cooling  purposes. 
40  gallons  of  castor  oil  are  run  into  the  tank,  and 
into  this  10  gallons  of  sulphuric  acid,  Twaddell- 
ing  170°,  are  very  slowly  poured;  the  mixture 
being  kept  constantly  stirred.  This  is  allowed  to 
stand  for  12  or  14  hours,  after  which  a  solution 
of  common  salt,  Twaddelling  about  8°,  is  run 
in,  well  mixed,  and  again  allowed  to  stand.  The 
fatty  acids  will  aggregate,  and  collect  at  the  surface 
of  the  salt  liquor.  This  liquor  is  then  drawn  off  by 
means  of  a  tap  placed  near  the  bottom  of  the  tank. 
The  operation  of  salting  is  repeated,  and  the  mixture 
again  allowed  to  settle,  the  salt  liquor  being  drawn 
off  as  before.  By  the  time  the  second  washing  has 
been  completed  practically  the  whole  of  the  sulphuric 
acid  should  have  been  removed.  It  is  now  necessary 
to  neutralise  the  free  acids  and  make  up  to  the 
desired  strength.  Caustic  soda  is  usually  the  alkali 
employed  for  this  purpose.  Some  manufacturers 
claim  that  liquid  ammonia  is  better,  and  for  certain 
work,  particularly  in  calico  printing,  this  probably  is 
so,  as  the  ammonia  salts  are  more  readily  decomposed 


198       The  Chemistry  and  Practice  of  Sizing. 

during  the  steaming  process,  thus  enabling  the 
colour  to  take  up  the  fatty  acids  more  readily.  In 
other  cases,  it  is  customary  to  almost  neutralise  with 
caustic  soda  solution,  and  complete  the  process 
by  the  careful  addition  of  liquid  ammonia.  Care  is 
required  in  the  operations  involved. 

When  the  fatty  acids  have  been  neutralised,  the 
"oleine"  is  diluted  to  a  certain  strength  with  water. 
The  standard  strength  generally  contains  50  per 
cent,  of  fatty  matter.  The  "oleine"  is  made  entirely 
soluble  by  means  of  a  solution  of  ammonia  which 
is  added  until  the  "oleine"  becomes  quite  clear. 

"Oleine"  oil  is  chemically  a  salt  of  sulphoricin- 
oleic  acid,  C18H23(HS08)03  Sometimes  it  is  the 
ammonium  salt,  but  generally  it  is  a  mixture  of 
ammonium  and  sodium  salts,  according  to  the 
method  of  preparation. 

"Oleine"  oil,  being  soluble  in  water,  may  be  used 
to  advantage  in  very  light  sizing  where  it  is  desired 
to  preserve  the  lustre  of  the  fabric.  In  such  cases  it  is 
used  in  conjunction  with  white  dextrin  and  starch. 
"Oleine"  oil  must  not  be  used  as  an  ingredient  of  the 
size  if  zinc,  calcium,  or  magnesium  salts,  are  present. 

SOLUBLE  OIL. 

This  preparation  is  usually  made  from  castor  oil. 
Occasionally  maize  or  other  oils  are  used,  but  the 
product  is  not  equal  in  quality  to  that  made  from 


Soluble  Oil 


castor  oil.  Soluble  oil,  made  from  castor  oil,  is 
really  a  castor  oil  soap.  It  is  prepared  by  boiling 
castor  oil  with  a  solution  of  caustic  soda.  The 
soluble  oil  should  be  free  from  alkali,  any  excess  of 
this  substance  being  neutralised,  either  by  the 
addition  of  more  castor  oil,  or  by  the  cautious 
addition  of  acetic  acid  to  the  hot  solution. 

The  following  proportions  of  the  ingredients 
may  be  used  in  the  preparation  of  soluble  oil  : — 

SOLUBLE  OIL. 

Castor  Oil    2  gallons. 

Caustic  Soda  Solution  at  400  T.   9  pints. 

Boil  the  above  for  one  hour  and  then  add 
Hot  Water   7  gallons. 

Soluble  oil  is  occasionally  used  as  a  u  softener" 
in  sizing. 

"  STEARINE'  —  Stearic  Acid. 

The  "Stearine"  of  commerce,  and  the  one 
employed  in  sizing,  generally  consists  of  a  mixture 
of  free  stearic  and  palmitic  acids.  Sometimes  oleic 
acid  is  also  present. 

"Stearine"  is  largely  prepared  from  cotton  seed 
oil.  It  is  a  bye-product  in  the  purification  of  this 
substance.  The  oil  is  agitated  with  a  10  or  15  per 
cent,  solution  of  caustic  soda  at  the  ordinary  tem- 
perature. The  alkali  combines  with  the  colouring 
matter,  and  at  the  same  time  saponifies  the  free 
fatty  acids.    This  colouring  matter,  with  the  soap,  is 


200      The  Chemistry  and  Practice  of  Sizing. 


deposited.  After  the  purified  oil  has  been  removed, 
the  deposit  is  treated  with  sufficient  sulphuric  acid 
to  decompose  the  soap.  The  fatty  acids  liberated 
are  then  heated  with  concentrated  sulphuric  acid  to 
about  250°  Fah.  This  treatment  renders  the 
colouring  matters  insoluble,  and  the  fatty  acids  float 
on  the  surface  of  the  mixture.  They  are  then 
removed,  and  distilled  with  superheated  steam. 
The  stearic  acid  is  generally  separated  from  the 
mixture  of  stearic  and  oleic  acids  by  pressure. 

Stearic  acid  is  frequently  adulterated  with  mineral 
oil  and  paraffin  wax,  for  which  substances  it  should 
be  tested  by  the  methods  described  under  tallow. 
It  is  itself  used  as  an  adulterant  of  tallow. 

Stearic  acid,  free  from  oleic  acid,  melts  at  about 
158°  Fah.,  but  this  is  not  the  ordinary  commercial 
form  as  used  for  sizing  purposes. 

PURE  STEARIN. 
This  substance  is  entirely  different  from  the 
"stearine"  of  commerce.  It  constitutes  the  less 
fusible  portion  of  solid  fats  such  as  tallow,  and  is 
known  chemically  as  tristearin,  or  glycyl  tristearate. 
It  occurs  largely  in  conjunction  with  tripalmitin  and 
triolein  in  the  natural  fats.  When  tristearin  is 
decomposed  with  caustic  alkalies,  glycerine  is  formed. 
C3H5(C18H3502)3    +    3KHO  = 

Stearin  (Glycyl  tristearate).       Caustic  Potash, 

3K(C1SH,50,)    +  C3Hs(HO)8 

Stearate  of  Potash  (Soap).  Glycerine. 


Spermaceti, 


201 


SPERMACETI, 

Spermaceti  is  fairly  extensively  used  as  a 
"softener"  in  some  districts.  Why  this  is  so  is  more 
than  the  authors  can  say.  In  the  first  place,  it  is  far 
too  expensive  a  substance  to  employ  for  such  a  pur- 
pose, and  in  the  second  place,  it  is  generally  used  in 
conjunction  with  tallow  and  paraffin  wax,  but  in  so 
small  a  proportion  to  the  total  quantity  of  size 
present,  that  any  special  properties  it  may  possess 
are  utterly  lost.  The  use  of  spermaceti  is  merely  a 
superstition,  and  its  qualities  may  be  equalled  by 
using  a  mixture  of  tallow  and  paraffin  wax,  or  by 
using-  either  of  these  substances  alone. 

Spermaceti  exists  in  solution,  in  the  oil  from  the 
sperm  whale,  and  other  cetaceans,  except  the  whale- 
bone whales.  It  occurs  most  abundantly  in  the  oil 
obtained  from  the  head  cavities,  and  in  a  lesser 
degree  from  the  blubber. 

Spermaceti  is  a  snow-white  substance  of  marked 
crystalline  structure.  It  melts  from  about  110  to 
i2o°  Fah.  It  is  very  liable  to  adulteration,  the 
chief  substances  used  for  this  purpose  being 
stearic  and  palmitic  acids,  "stearine,''  tallow7,  and 
paraffin  wax.  The  fatty  acids  may  be  detected  by 
determining  the  amount  of  fatty  acids  present  in  the 
sample,  as  described  on  page  186;  anything  above 
i  per  cent,  indicates  adulteration  with  these  sub- 
stances. Tallow  and  "stearine"  may  be  detected 
by  the  smell  produced  on  heating  the  sample.  The 


202       The  Chemistry  and  Practice  of  Sizing. 


proportion  of  these  substances  may  be  determined 
by  treating  with  standard  alcoholic  potash  solution 
and  standard  HC1  as  described  on  page  1 88. 

Paraffin  wax  lowers  the  density  of  spermaceti, 
this  being,  in  the  case  of  true  spermaceti,  '942  to 
•946  at  6o°  Fah.,  whilst  in  the  case  of  paraffin 
wax,  it  is  '909.  The  presence  of  paraffin  wax 
would  also  lessen  the  percentage  of  caustic  potash 
required  to  saponify  spermaceti,  the  amount  required 
for  the  pure  substance  being,  on  an  average,  12*8 
per  cent. 

PARAFFIN  WAX. 

Paraffin  wax  is  obtained  in  the  manufacture  of 
paraffin  and  petroleum.  In  the  crude  state  it  is  a 
brownish  soft  scaley  substance,  and  should  never  be 
used  for  sizing  unless  purified.  Paraffin  wax  varies 
greatly  in  quality,  the  quality  depending  upon  the 
melting  point.  A  good  class  wax  for  sizing  purposes 
melts  at  from  120°  to  125°  Fah.  For  pharmaceutical 
purposes  a  much  higher  melting  point  is  required, 
viz.: — 130°  to  140°  Fah.,  but  this  wax  is  too  dear 
for  ordinary  commercial  use. 

Usually  four  qualities  of  wax  are  manufactured, 
the  best  commercial  samples  melt  at  120°  to  1250 
Fah,,  the  second  11 5°  to  120°  Fah.,  the  third  at 
1  io°  to  1 1 5°  Fah.,  and  the  fourth  at  ioo°  Fah. 

Paraffin  wax  gives  off  vapour  at  low  tempera- 
tures, the  temperature  depending  upon  the  quality 


Paraffin  Wax. 


203 


of  the  wax.  The  average  vaporising  point  is  from 
2  io°  to  220°  Fah. 

Paraffin  wax  is  very  extensively  used  in  sizing, 
but  it  should  never  be  used  where  the  cloth  is 
intended  to  be  bleached,  dyed,  or  printed.  Paraffin 
wax  is  unsaponifiable,  and  consequently  it  cannot 
be  removed  by  boiling  with  caustic  soda,  lime,  or 
soda  ash.  The  mechanical  action  of  boiling  may 
remove  a  certain  quantity  of  the  wax,  if  the  liquor 
in  the  kiers  is  discharged  at  the  top  by  forcing  fresh 
water  in  at  the  bottom,  But  if,  as  is  usually  the 
case,  the  liquor  is  run  off  from  the  bottom,  the  bulk 
of  the  paraffin  wax  will  settle  on  the  cloth  at  the  top 
of  the  kier.  This  will  give  rise  to  patchy  places  in 
the  dyed  and  finished  fabrics.  Even  where  there  is 
a  trace  only  of  paraffin  wax  left  in  the  cloth  the 
colour  will  not  take  evenly  when  the  fabric  is  dyed 
or  printed. 

Paraffin  wax  is  largely  used  for  sizing  coloured 
yarns  for  dhootie  bordered  goods.  It  lays  the 
fibres  of  the  yarn  rather  better  than  tallow,  and, 
as  these  yarns  are  generally  sized  with  as  small 
a  percentage  of  size  as  possible,  it  enables  them 
better  to  resist  the  rubbing  of  the  healds  and 
reed. 

Occasionally  cloth  sized  with  a  mixing  containing 
paraffin  wax  becomes  yellow  on  keeping.  This 
objectionable  colour  is  due  to  the  fact  that  the  wax 
has  not  been  sufficiently  refined. 


204      The  Chemistry  and  Practice  of  Sizing. 


JAPAN  WAX. 

Japan  wax  is  obtained  from  the  berries  of  several 
species  of  Rhus.  The  crude  wax  is  obtained  in 
greenish  tallow-like  masses,  and  is  purified  by 
filtration  and  bleaching.  Purified  Japan  wax  is 
yellowish-white  in  colour,  and  it  has  a  melting  point 
of  from  1230  to  1 28°  Fah.  Japan  wax  may  be 
saponified  by  boiling  with  caustic  soda  and  caustic 
potash.  By  this  treatment  it  yields  fatty  acids  and 
glycerine.  Japan  wax  is  occasionally  used  in  sizing. 
It  is  frequently  combined  with  caustic  soda  and 
water,  to  form  a  soap.  This  soap  is  usually  sold  in 
the  form  of  a  paste,  and  it  is  mainly  used  for  sizing 
woven  coloured  goods,  such  as  flannelettes,  etc. 
These  preparations  generally  contain  an  excess 
of  wax,  dissolved,  or  emulsified,  in  the  wax  soap. 

Japan  wax  is  readily  saponified  in  the  bleaching 
operations  when  subjected  to  the  lime  boil.  For 
this  reason  it  may  be  used  for  goods  intended  to 
be  bleached. 


3  IN  SIZING. 

Other  characteristics. 

Commercially  pure  tallow  rarely 
melts  below  108°Fah.,  generally 
from  110°  to  118°  Fah. 

Brownish  or  dirty  white  in  colour, 
unpleasant  smell,  generally  con- 
tains phosphate  of  calcium. 

Creamy    white   in    colour,  not 
unpleasant  smell,  granular  ap- 
pearance,   generally  contains 
phosphate  of  calcium. 

Characteristic  smell  of  stearic  acid 
on  heating;  consists  of  a  mixture 
of  stearic  and  palmitic  acids. 

White,    consistency   of  butter, 
characteristic  smell  of  cocoa-nut. 

Natural  colour,  brownish  yellow 
to  deep  orange   red;  always 
bleached  for  sizing  purposes. 

Very  viseuous,  high  specific  gravi- 
ty, forms  an  ether  with  sulphuric 
acid. 

Pure  white  in  colour,  with  charac- 
teristic crystalline  appearance. 

USE! 

Percentage 
of  insoluble 
Fatty  Acids, 
combined 
and  free. 

v£> 

ON 

O 
LO 

ON 

vO 

ON 

v£> 

ON 

Varies 

00 
00 
C 

ro 
00 

LO 

MO 
ON 

ON 

ro 

LO 
O 

CS 

LO 

AND  WAXES 

Average 
Saponifica- 
tion 

Equivalent. 

o 

ON 
CS 

o 

ro 
00 
CS 

Tj- 

ON 

CS 

-r 

ON 

CS 

Varies 

O 

LO 

CS 

0 

ON 

0 

CS 

VO 
00 
CS 

0 

CS 

ON 

ro 
O 

ON 
O 

ro 

5- 

O 

CS 

ro 

vS* 
CS 
O 

LTl 
LO 

CS 

Percentage  of 
Caustic  Potash 

(KHO)  for 
Saponification. 

p 
b 

CS 
O 

vp 

ON 

LO 

ON 

LO 

ON 

Varies 

0 

oc 

vO 
CS 

0 
0 

Vf 

CS 

0 
p 

CS 

0 

ro 

ON 

LO 

00 

0 
0 

vp 

r->. 

ro 
O 
ro 
CS 

LO 

CS 
CS 
CS 

0 
5 

CS 

OILS, 

Melting 
Point  in 
degrees  Fah. 

00 

o 

CO 

o 

o 

O 

ON 

V 

o 
o 

ON 

Varies 
according  to 
composition. 

~cs 

00 

0 

00 

0 

v£> 

ON 

0 

°o 

CS 

0 
°o 

0 
CS 

0 

0 
CS 
CS 

FATS, 

Gravity. 
Fah.=1000. 

0 

o 
1— 1 

<q 

86o  to  862 

00 
0 

00 

00 

ON 
LO 

00 

0 

LO 

00 

ON 
O 

ON 

CS 
CO 

0 

00 

0 

00 

00 

0 
00 

N  OF 

Specific 
Water  at  60° 

A 

03 

0 

o 
< 

ro 

ON 

O 
CS 

ON 

0 

ro 
ON 

CS 

ON 
O 

O 
CS 

ON 

O 

On 
O 

O 

LO 

ON 

vO 

ON 

O 

CS 

ON 

O 
0 
O 

0 
00 

ON 

ificatio: 

Source. 

From  ox  &  sheep 

Bones  of  various 
animals 

Bones  of  various 
animals 

Cotton  seed  oil, 
see  page  199 

Nuts  of  cocos 
nucifei'a 

Fruit  of  eleais 
guineenis 

O  ft 

WJ  ft 

T3  ^ 

CD 

<V 
CO 

From  oil  of 
sperm  whale 

O  « 
tri  \. 
CD  ^ 

CLASS 

Nature  of 
Substance. 

TALLOW 

BONE  FAT  ... 

MARROW  FAT 

PC  0 

3 - 

H  co 
CO  — 

COCOA-NUT 
OIL 

PALM  OIL  ... 

CASTOR  OIL 

SPERMACETI 

JAPAN  WAX... 

2o6       The  Chemistry  and  Practice  of  Sizing. 


Chapter  IV. 

Soap. 


HIS  substance,  either  in  the  form  of  hard  or 
soft  soap,  is  very  extensively  used  in  sizing. 


Soap  is  produced  by  boiling  tallow,  or  some 
other  form  of  animal,  vegetable,  or  fish  oil,  in  a 
solution  of  caustic  soda  or  potash. 

All  fats  and  oils,  other  than  hydrocarbon  oils, 
and  to  a  certain  extent  sperm  oil,  are  combinations 
of  fatty  acids  with  glycerine.  Caustic  potash 
and  soda  have  the  powers  of  decomposing  this 
combination.  The  alkali  unites  with  the  fatty  acids, 
producing  soap  with  the  formation  of  glycerine. 
Other  substances,  such  as  oxide  of  lead,  alumina, 
lime,  etc.,  have  this  power  of  decomposing  fats  and 
oils,  but  in  these  cases  insoluble  soaps  are  produced. 
A  typical  instance  of  an  insoluble  soap  is  ordinary 
sticking  plaster.  This  is  an  oleate  of  lead,  and  it  is 
produced  by  boiling  oxide  of  lead  with  olive  oil. 

Commercial  soaps  may  be  divided  into  two 
distinct  classes,  viz  : — Hard  soaps  and  soft  soaps. 
The  former  are  combinations  of  fats  or  oils  with 
caustic  soda,  whilst  the  latter  are  combinations  of 
oils  with  caustic  potash. 


Soap.  207 

HARD  SOAP. 

Hard  soap  is  manufactured  in  enormous 
quantities  in  this  country. 

The  following  short  description  will  give  the 
reader  some  idea  of  the  processes  used  in  soap 
boiling  : — The  tallow,  or  other  fat  to  be  saponi- 
fied, is  introduced  into  the  boiler,  and  the 
caustic  lye  added,  after  which  the  mixture  is 
gently  heated  to  the  boiling  point,  As  a  rule  a 
quantity  of  soap  is  added  to  the  mixture  in  order  to 
emulsify  the  fat,  thus  making  it  combine  more 
readily  with  the  alkali.  After  the  mixture  has 
boiled  for  a  few  hours,  it  forms  a  viscid  emulsion, 
capable  of  being  drawn  out  into  thin  threads.  The 
soap  in  this  emulsion  is  now  in  solution  in  the  water, 
but  the  whole  of  the  fat  has  not  become  completely 
saponified.  In  order  to  effect  this  the  soap  and 
uncombined  fat  must  be  separated  from  the  spent 
lye,  so  that  a  fresh  solution  of  alkali  can  be 
added.  For  this  purpose  a  quantity  of  common 
salt  is  added.  This  dissolves  in  the  water,  and 
causes  the  soap  and  unsaponified  fat  to  rise  to 
the  surface.  The  operation  of  boiling  with  caustic 
lye  is  repeated  to  complete  the  saponification, 
and  the  soap  separated  as  previously  described. 
It  is  then  allowed  to  partially  cool,  and  after- 
wards ladled  out  into  buckets  and  conveyed 
to  the  frames  in  order  to  completely  cool 
and  set. 


208      The  Chemistry  and  Practice  of  Sizing. 

The  following  analyses  give  some  idea  of  the 
average  composition  of  white  hard  soap.  It 
may  be  well  to  state  here  that  soap  made  from 
cocoa-nut  oil  will  retain  more  water  and  remain 
harder  than  that  made  from  any  other  oil  or  fat. 


Variety  of  Soap. 

Fatty 

Dry 

Acids. 

Soda. 

Water 

Analyst. 

per  cent. 

per  cent 

per  cent. 

Castile  soap  ,  

76-S 

90 

145 

Ure. 

Castile  soap  

75'2 

10  5 

14*3 

)> 

White  toilet  soap  

75*° 

9-0 

i6'o 

)? 

Ordinary  white  soap  

6o*o 

6-4 

33*6 

5) 

76*0 

8-9 

Percy  Bean. 

2  2*0 

4'S 

73*5 

Ure 

Good  white  tallow  soap... 

76-3 

8-9 

14-8. 

Percy  Bean. 

50-2 

4*6 

45*^ 

Thenard 

Tallow  substitute,  No.  i... 

23*4 

4-28 

72-32 

Percy  Bean. 

do.        do.       No.  2... 

6-86 

2*69 

9°'45 

>> 

do.        do.       No.  3... 

18-30 

4*20 

7i*5° 

>> 

It  will  be  seen  that  good  hard  soaps  contain 
from  60  to  76  per  cent,  of  fatty  acids,  and  in  very 
dry  samples  which  have  been  kept  some  years,  as 
much  as  81  per  cent,  has  been  found  by  the  writer. 
The  tallow  substitutes  have  been  included  under 
soaps,  in  order  to  make  a  comparison  of  their 
values.  The  sample  No.  3  contained  small  quantities 
of  glycerine  and  gum  in  addition  to  the  substances 
enumerated. 


Soft  Soap. 


209 


SOFT  SOAP. 

Soft  soap  is  produced  by  boiling  caustic  potash 
with  oil,  such  as  hemp  seed,  linseed,  or  fish  oil,  etc. 
The  nature  of  the  oil  employed  is  indicated  by  the 
smell  or  colour  of  the  soap.  Generally  hemp  seed 
oil  produces  a  soft  soap  which  possesses  a  rich  green 
colour.  Linseed  oil  soap  is  brown,  whilst  fish  oil 
soaps  are  easily  recognised  by  their  smell.  Soft 
soaps  always  remain  soft  if  prepared  from  caustic 
potash,  and  they  are  less  often  adulterated  than  hard 
soaps.  Any  addition  of  water  would  be  evident  by 
the  fluid  condition  of  the  soap.  Occasionally  the 
writer  has  come  across  soft  soap  adulterated  with  a 
large  quantity  of  silicate  of  soda.  These  soaps  have 
been  poor  in  appearance,  and  very  often  a  large 
amount  of  a  slimy  deposit  is  found  at  the  bottom  of 
the  cask.  Soap  containing  silicate  of  soda  should 
not  be  used  for  sizing  purposes. 

Soft  soaps  are  hygroscopic,  z>.,  they  absorb  water 
from  the  atmosphere.  Hard  soaps,  on  the  other  hand, 
give  off  their  excess  of  water,  losing  considerably  in 
weight.  These  properties  are  very  characteristic  of 
other  potash  and  soda  salts.  Carbonate  of  soda  or 
washing  soda  gives  off  its  water  of  crystallisation, 
whilst  carbonate  of  potash  absorbs  water. 

Many  manufacturers  judge  the  value  of  a  soft 
soap  by  its  appearance,  and  take  as  a  standard  the 
transparency  of  the  green  or  brown  mass,  and  the 
amount  and  appearance  of  white  granules  contained 

N 


210       The  Chemistry  and  Practice  of  Sizing. 

therein.  The  latter  appearance  is  known  in  the 
trade  as  "  figging."  The  granules  are  produced  by 
adding  tallow  to  the  soap  just  before  the  boiling 
operation  is  completed.  The  tallow  forms  stearate 
of  potash.  These  granules  make  their  appearance 
only  after  the  soap  has  been  manufactured  for  some 
time,  and  in  hot  weather  they  are  not  produced  at  all. 
The  probability  is  that  this  appearance  of  " figging" 
has  been  made  a  standard  of  quality  by  buyers, 
because  certain  firms  of  soap  makers,  who  have  a 
good  reputation,  have  affected  this  class  of  soap,  and 
consequently  it  has  got  a  good  name.  Unfortunately, 
inferior  soaps  have  been  put  upon  the  market,  and 
starch  has  been  used  to  produce  the  desired 
"figging"  effect,  consequently  this  peculiar  appear- 
ance must  not  always  be  looked  upon  as  a  sign  of 
good  quality. 

In  the  manufacture  of  soft  soap,  the  soap  is  not 
separated  from  the  lye,  as  is  the  case  in  the  manu- 
facture of  hard  soaps,  the  main  object  in  the 
production  of  soft  soap  is  to  combine  the  caustic 
potash  with  the  fat  or  oil.  Soft  soaps,  therefore, 
contain  the  whole  of  the  base  of  the  oils,  i.e., 
the  glycerine,  as  well  as  the  impurities  existing  in 
the  lye,  such  as  carbonate,  chloride,  and  sulphate 
of  potassium,  etc.,  as  well  as  a  certain  amount 
of  free  caustic  potash.  Soft  soaps  always 
contain  more  water  and  free  alkali  than  ordinary 
hard  soaps. 


A nalysis  of  Soap.  2 1 1 

The  following  analyses  show  the  composition  of 
good  ordinary  soft  soaps. 


Variety  of  Soap. 

Fatty 
Acids, 
per  cent. 

Dry 
Potash, 
per  cent. 

Water, 
percent. 

Analyst. 

44-0 

9*5 

46-S 

Thenard. 

45'° 

8'5 

46'S 

Ure. 

Green  soft  soap  

36-0 

7-0 

57"o 

>) 

Scotch  soft  soap   

47  "o 

8-o 

45'° 

n 

5r6 

IO'O 

38-3 

>> 

Scotch  olive  oil  soap   

48-0 

IO'O 

42  0 

)> 

Ordinary  soft  soap,  No.  1 

44  "4 

9*3 

46-3 

Percy  Bean. 

do.       do.       No.  2 

42  6 

9-0 

48-4 

J? 

do.       do.       No.  3 

39'4 

8-8 

5r8 

Analysis  of  Soap. 

Soap  is  frequently  adulterated.  It  is  therefore 
necessary  that  it  should  be  systematically  analysed. 

The  following  process  is  simple,  and  suitable  for 
the  analysis  of  ordinary  hard  or  soft  soaps  (Muter)  : 
Cut  the  sample  across,  and  drop  on  the  fresh  surface 
a  solution  of  phenol-phthalein  in  alcohol,  when  any 
red  colour  shows  the  presence  of  free  alkali.  If  free 
alkali  be  found,  dissolve  5  grammes  in  absolute 
alcohol,  add  phenol-phthalein,  titrate  with  decinormal 
acid,  and  calculate  to  NaHO,  or  KHO,  according 
to  which  alkali  is  present. 

Dissolve  2  grammes  of  the  soap  in  absolute 
alcohol  by  the  aid  of  heat,  add  a  drop  of  phenol- 
phthalein  solution,  and  pass  C02  till  any  red  colour 


2 1 2       The  Chemistry  and  Practice  of  Sizing. 

disappears.  Filter  through  a  tared  filter,  and  wash 
any  insoluble  matter  found  with  warm  alcohol,  dry 
at  2 1 2°  Fah.,  and  weigh.  This  will  give  total  impuri- 
ties (such  as  alkaline  carbonates,  silicates,  or  borax). 
The  filtrate  and  washings  are  then  evaporated  on  the 
water  bath,  in  a  weighed  platinum  or  porcelain  dish, 
the  residue  being  dried  in  the  water  oven  to  constant 
weight,  and  weighed  =  actual  real  soap  present.  The 
dish  and  contents  are  then  gently  heated  to  redness, 
the  residue  left  being  dissolved  in  water,  and  titrated 
with  decinormal  acid,  using  methyl  orange  as  the 
indicator.  The  number  of  c.c.  used  is  multiplied  by 
•003 1  for  hard  soda  soaps,  or  by  '0047  for  soft  potash 
soaps,  and  the  resulting  amount  of  alkali  being 
deducted  from  the  weight  of  real  soap  found,  the 
difference  x  1 '03  =amountoffattyacids.  The  weights 
of  real  soap  and  total  impurities  added  together,  and 
deducted  from  2  (the  amount  of  soap  taken)  gives 
the  water  present  in  the  sample.  Finally,  everything 
is  calculated  to  a  percentage. 

As  a  general  rule  the  value  of  a  soap  for  sizing 
purposes  may  be  ascertained  by  determining  the 
amount  of  combined  fatty  acids  present. 

For  this  purpose  about  10  to  15  grammes  of  soap 
should  be  operated  upon.  In  the  case  of  hard  soap 
the  sample  should  be  cut  from  the  middle  of  the  piece, 
and  in  fine  shavings.  A  porcelain  evaporating  basin 
and  a  glass  rod  are  carefully  weighed  together,  the 
soap  added,  and  the  whole  weighed  again.  The 


Combined  Fatty  Acids  in  Soap.  213 


difference  in  weight  gives  the  amount  of  soap  taken. 
A  little  water  is  added,  and  the  basin  and  contents 
heated  on  the  water  bath  until  the  whole  of  the  soap 
has  dissolved.  Hydrochloric  acid  is  then  added,  and 
the  whole  well  stirred,  the  heating  being  continued 
for  a  few  minutes  longer.  The  hydrochloric  acid 
combines  with  the  soda  or  potash  of  the  soap  and 
liberates  the  fatty  acids,  which  float  on  the  top  of 
the  water.  The  basin  is  allowed  to  cool,  and  when 
thoroughly  cold,  the  cake  of  fat  should  be  lifted  out 
with  the  stirring  rod,  and  the  excess  of  hydro- 
chloric acid  and  water  poured  out.  (In  the  case 
of  soft  soap  the  fatty  acids  are  fluid,  and  it  is 
necessary  to  add  a  weighed  quantity  of  bees-wax 
in  order  to  solidify  them,  as  described  later).  Pure 
water  is  added,  and  the  cake  of  fat  re-melted  in 
order  to  wash  out  all  trace  of  hydrochloric  acid.  It 
is  again  allowed  to  cool,  the  fat  removed  as  before 
and  laid  upon  a  piece  of  clean  white  blotting  paper 
which  will  take  up  most  of  the  moisture.  The  water 
in  the  basin  is  now  poured  out,  taking  care  that  no 
particles  of  fat  are  lost.  The  bottom  and  sides  of 
the  basin  are  then  carefully  dried  with  blotting  paper, 
and  the  fat  replaced  and  carefully  heated,  If  any 
water  remains,  crackling  will  commence,  and  the 
melted  fat  must  be  rapidly  stirred,  to  prevent  spirt- 
ing, until  the  water  is  evaporated.  This  will  be 
evident  when  the  crackling  ceases.  The  whole 
should  be  allowed  to  cool,  and  then  carefully  weighed. 


2 1 4        The  Chemistry  and  Practice  of  Sizing. 

The  weight  of  the  basin  and  rod  deducted  from  the 
total  weight  gives  the  weight  of  fatty  acids  present  in 
the  soap.    This  should  be  calculated  to  a  percentage. 

Sometimes  the  fat  does  not  set  solid,  especially 
in  the  case  of  soft  soaps.  When  this  is  the  case,  5 
or  6  grammes  of  white  bees-wax  should  be  carefully 
weighed  and  added  to  the  hot  fatty  acids  and  water, 
the  whole  being  well  stirred  until  the  wax  and  fatty 
acids  are  mixed.  The  mixture  is  allowed  to  cool  as 
before,  and  washed  and  dried  as  described.  The 
weight  of  wax  must  be  added  to  the  weight  of  the 
evaporating  basin  and  glass  rod,  and  deducted  from 
the  total  weight,  the  difference  giving  the  proportion 
of  fatty  acids  combined  in  the  soap. 

Whenever  a  low  percentage  of  fatty  acids  is 
found  a  correspondingly  high  percentage  of  water 
may  be  expected.  The  amount  of  water  present  may 
be  roughly  ascertained  by  drying  a  carefully-weighed 
sample  of  the  soap  in  the  steam  oven  for  four  or  five 
hours.  The  loss  of  weight  represents  water,  but  not 
all  the  water.  It  is  near  enough,  however,  for  all 
practical  purposes.  The  same  precautions  should 
be  taken  in  making  the  weighings  for  estimation  of 
moisture  as  described  under  flour. 

Use  of  Soap  in  Sizing. 

The  value  of  soap  as  a  sizing  ingredient  depends 
entirely  upon  the  object  for  wThich  it  is  used,  and 
also  to  the  presence  or  absence  of  certain  ingredients. 


Use  of  Soap  in  Sizing. 


215 


Soap  has  the  power  of  readily  dissolving  tallow,  and 
so  causes  the  fat  to  mix  better  with  the  flour  or 
other  starchy  matter.  It  is  also  claimed  that  soap 
causes  China  clay  to  boil  thinner,  and  at  the  same 
time  prevents  the  clay  from  spirting.  The  latter 
result  is  of  no  practical  value  as  it  is  only  necessary 
to  place  a  lid  over  the  clay  pan  to  prevent  spirting. 

For  light  sizing,  soap  is  a  most  useful  ingredient 
but  it  should  never  be  used  if  chloride  of  magnesium, 
sulphate  of  magnesium,  chloride  of  calcium,  or  chloride 
of  zinc,  are  ingredients  of  the  size.  These  substances 
decompose  soap,  with  loss,  both  to  the  properties  of 
the  salts  themselves,  and  to  the  utter  destruction  of 
the  properties  peculiar  to  soap.  If  magnesium  and 
zinc  salts  are  in  excess,  the  whole  of  the  soap  is 
converted  into  a  magnesium  or  zinc  soap,  which 
differs  entirely  from  the  original  soap.  Its  power  of 
emulsifying  fat  is  lost,  and  instead  of  being  useful 
as  a  11  softener,"  it  becomes  harsh  and  difficult  to 
mix  with  the  size.  In  other  words,  the  use  of  soap 
in  medium  and  heavy  sizing  is  an  absolute  loss, 
and  needless  expense. 

As  previously  stated,  soft  soap  possesses  deli- 
quescent properties  and  for  this  reason  it  is  a  more 
suitable  substance  to  use  in  sizing  than  hard  soap. 

In  conclusion  it  may  be  as  well  to  warn  manu- 
facturers against  the  use  of  soft  soaps  prepared  from 
fish  oils.  They  usually  possess  a  very  strong  and 
objectionable  smell  which  is  imparted  to  the  cloth, 


2 1 6       The  Chemistry  and  Practice  of  Sizing. 


and  this  smell  becomes  intensified  according  to  the 
length  of  time  the  cloth  is  kept.  The  writer  knows 
of  many  instances  where  cloth  has  been  rejected  on 
account  of  its  objectionable  smell,  due  to  the  use  of 
soft  soap  prepared  from  fish  oil. 


Deliquescent  Substances. 


217 


Chapter  V. 

Deliquescent  Substances, 
used  for  softening  and  for  giving 
strength  and  weight  to  the  Yarn. 


THIS  class  of  sizing  ingredients  is  in  general 
use  where  much  weight  of  size  has  to  be  put 
on  the  yarn.  It  is  evident  that  where  a  large  amount 
of  starchy  matter  and  mineral  matter  are  constituents 
of  a  size  mixture,  some  substance  must  be  used  to 
counteract  the  harshness,  and  consequent  tendency 
to  bad  weaving,  which  is  produced. 

The  following  are  the  most  important  of  these 
substances: — Chloride  of  magnesium,  chloride  of 
calcium,  and  glycerine.  They  are  highly  hygro- 
scopic bodies,  and  by  their  powers  of  absorbing 
moisture  from  the  atmosphere  of  the  weaving  shed 
they  soften  the  yarn,  and  at  the  same  time  greatly 
strengthen  it,  thus  enabling  it  to  weave  easily 
and  well. 


2  1 8       The  Chemistry  and  Practice  of  Sizing. 


CHLORIDE  OF  MAGNESIUM— 

"  Antiseptic." 

Chloride  of  magnesium  is  the  most  important 
deliquescent  substance  used  in  sizing.  It  received 
the  name  of  "  antiseptic  "  when  it  first  came  into  use. 
Why  this  name  came  to  be  given  to  it  the  authors  are 
at  a  loss  to  understand.  Its  properties  in  cloth  are  en- 
tirely the  reverse  of  those  of  a  true  antiseptic.  Instead 
of  preventing  the  growth  of  mildew,  it  has  a  strong 
tendency  to  assist  it.  The  substance  itself  does  not 
mildew,  but,  on  account  of  its  power  of  absorbing 
moisture,  it  causes  the  starchy  matter  to  do  so,  unless 
there  be  present  some  real  antiseptic  substance  such 
as  chloride  of  zinc.  The  authors  feel  that  this-  book 
will  have  been  of  some  little  service  if  it  only  helps 
to  kill  that  most  misleading  term,  "antiseptic,"  as 
applied  to  chloride  of  magnesium. 

There  is  no  doubt  that  the  numerous  cases  of 
mildew  which  occurred  20  or  30  years  ago  were  due 
to  the  use  of  this  chemical  by  manufacturers  who  did 
not  know  its  true  action  and  properties. 

Chloride  of  magnesium  is  a  compound  of  the 
metal  magnesium  with  chlorine  gas,  having  the 
formula  MgCl2.  It  crystallises  in  needle-shaped 
crystals,  having  the  following  composition  : — 

Per  cent. 

Chloride  of  Magnesium  (real)...  46*80 
Water  of  crystallization    5 3* 20 

ioo'oo 


Chloride  of  Magnesium. 


Commercial  chloride  of  magnesium  is  very  nearly 
pure,  as  the  natural  chloride  of  potassium  found  with 
it  is  too  valuable  a  substance  to  be  left  unrecovered, 
and  it  is  therefore  carefully  removed. 

Chloride  of  magnesium  is  produced  in  larpe 
quantities  at  the  salt  mines  of  Stassfurt,  in  Prussia, 
where  it  occurs  as  the  mineral  "carnallite."  This 
mineral  has  the  following  composition  when  pure, 
and  may  be  looked  upon  as  a  double  salt  of 
magnesium  and  potassium,  having  the  formula, 
MgCl2KCl,6H20. 

Per  cent. 

Chloride  of  magnesium    34-5 

Chloride  of  potassium    2676 

Water   3874 

IOO'OO 

The  chloride  of  potassium  is  separated  from  the 
chloride  of  magnesium  by  crystallisation.  The 
potassium  salt  is  less  soluble  than  the  magnesium 
salt,  and  it  therefore  crystallises  out  of  solution, 
leaving  the  magnesium  salt  in  solution  in  the  mother 
liquor.  The  liquor  is  drained  off  from  the  potassium 
chloride  crystals,  after  which  it  is  evaporated  down 
to  a  certain  specific  gravity.  It  is  then  run  into 
casks,  where  it  crystallises  into  solid  masses.  In 
this  state  it  is  sent  to  England. 

•'Carnallite"  is  not  found  pure  in  nature,  and  there 
is  often  present  small  quantities  of  chloride  of  cal- 
cium, and  the  sulphates  of  soda,  potash  and  lime. 


220       The  Chemistry  and  Practice  of  Sizing. 

Most  of  these  impurities  are  removed  by  re-crystallis- 
ation, but  there  is  generally  a  trace  left.  The 
following  analysis  represents  a  fair  average  sample 
of  the  chloride  of  magnesium  of  commerce  : — 

Per  cent. 

Chloride  of  magnesium    46*40 

Chlorides  of  sodium  and  potassium  ...  1*98 

Sulphates  of  potash  and  soda    '94 

Water   50*68 

ioo'oo 

Chloride  of  magnesium  is  also  manufactured  in 
England  by  dissolving  carbonate  of  magnesium  in 
hydrochloric  acid.  The  greatest  care  must  be  taken 
that  no  free  acid  is  left  in  the  finished  article. 

This  prepared  chloride  of  magnesium  is  generally 
sold  in  the  form  of  a  liquid,  and  some  very  good 
samples  have  passed  through  the  writer's  hands. 
It  is  necessary  to  take  the  specific  gravity  of  this 
liquid  to  ensure  getting  the  right  strength.  The 
English  chloride  of  magnesium  generally  contains 
about  30  per  cent,  of  real  chloride  of  magnesium, 
as  against  46  per  cent,  in  the  solid  German  chloride. 

Although  chloride  of  magnesium  is  rarely  adul- 
terated wilfully,  it  is  necessary  to  apply  the 
following  tests. 

(1)  Sulphates. — A  small  portion  of  the  salt  is 
dissolved  in  distilled  water,  and  filtered  if  not  clear. 
A  few  drops  of  hydrochloric  acid  and  a  few  drops  of 
barium  chloride  are  then  added.  If  a  white  precipitate 


Impurities  in  Chloride  of  Magnesium.      2  2 1 

forms,  sulphates  are  present.  Most  samples  of 
chloride  of  magnesium  will  show  a  slight  white  pre- 
cipitate, but  this  may  be  ignored. 

(2)  Chloride  of  Sodium. --Common  Salt. — 
A  portion  of  the  chloride  of  magnesium  is  dissolved 
in  a  test  tube,  with  as  little  distilled  water  as  possible. 
To  this  solution  should  be  added  twice  its  volume 
of  strong  hydrochloric  acid.  The  mixture  should 
be  well  shaken  up.  If  salt  be  present  as  an 
adulterant,  it  will  be  precipitated,  on  account  of  the 
insolubility  of  common  salt  in  hydrochloric  acid. 
If  common  salt  be  not  shown  by  this  test,  the  sample 
may  be  passed  as  free.  The  test,  frequently 
advised,  of  burning  a  portion  on  the  end  of  a 
platinum  wire  in  order  to  obtain  the  characteristic 
sodium  flame  (an  intense  yellow)  is  useless,  as  the 
slightest  trace  of  salt  is  shown  by  this  test. 

In  testing  chloride  of  magnesium  for  common  salt 
traces  may  be  ignored,  as  people  do  not  adulterate  in 
traces.  The  special  value  of  this  test  is  apparent, 
because  it  passes  over  traces  and  detects  adulter- 
tions.  Its  value  is  more  apparent  in  the  case 
of  chloride  of  zinc.  This  substance  is  much  more 
liable  to  adulteration  with  common  salt  than  is 
chloride  of  magnesium. 

(3)  Chloride  of  Calcium. — This  substance  is 
frequently  used  as  an  adulterant  in  the  liquid  form 
of  chloride  of  magnesium.  It  is  very  cheap,  being 
a  waste  product  in  certain  chemical  manufacturing 


222       The  Chemistry  and  Pi'actice  of  Sizing. 

processes,  and  it  often  contains  very  objectionable 
impurities,  such  as  chloride  of  iron,  and  not  un- 
commonly hypochlorite  of  calcium.  In  order  to 
test  for  calcium  it  is  necessary  to  add  to  the 
suspected  solution,  chloride  of  ammonium  ih  excess, 
then  a  few  drops  of  solution  of  ammonia,  and  finally 
a  solution  of  oxalate  of  ammonium.  A  white 
precipitate  will  be  formed  if  chloride  of  calcium  be 
present.  If  the  amount  of  the  adulterant  be 
required,  the  sample  should  be  analysed  in  the  usual 
way  for  calcium.  Although  chloride  of  calcium, 
when  free  from  objectionable  impurities,  may 
possibly  be  as  good  as  chloride  of  magnesium  for 
some  purposes,  the  sizer  who  has  bought  chloride 
of  magnesium,  should,  under  no  circumstances,  use 
a  mixture  containing  a  large  quantity  of  chloride  of 
calcium  as  it  might  change  the  entire  character 
of  a  mixing. 

Sometimes  chloride  of  magnesium  contains 
chloride  of  iron  as  an  impurity.  This  is  a  very 
objectionable  substance  to  have  present,  as  it  may 
give  rise  to  iron-stains  on  the  cloth.  The  method 
of  testing  for  iron  is  given  under  chloride  of  zinc. 

The  presence  of  acid  should  always  be  tested  for 
by  means  of  blue  litmus  paper,  as  described  on 
page  34.  Acid  is  more  likely  to  be  found  in  the 
manufactured  salt  than  in  the  natural  German 
chloride  of  magnesium. 

When  chloride  of  magnesium  is  strongly  heated 


Action  of  Heat  on  Chloride  of  Magnesium.  223 

hydrochloric  acid  is  liberated,  consequently  it 
should  never  be  used  for  fabrics  which  are  intended 
for  bleaching,  unless  its  presence  is  declared  by 
the  manufacturer.  In  the  bleaching  operation  the 
goods  are  subjected  to  a  great  heat  duringMhe 
process  of  singeing.  This  heat  is  sufficient  to 
decompose  the  chloride  of  magnesium,  and  the 
liberated  hydrochloric  acid  will  very  quickly  attack 
the  fibre  of  the  cotton  and  destroy  it.  Numerous 
cases  of  damage  come  under  the  writers  notice 
from  the  use  of  chloride  of  magnesium  in  goods 
which  have  undergone  the  operation  of  singeing. 

If  the  presence  of  magnesium  chloride  was 
declared  by  the  manufacturer  it  could  be  removed 
by  washing  and  drying  the  cloth  previous  to  singeing. 
This  would  add  some  cost  to  the  bleaching  opera- 
tion, but  it  might  be  worth  the  while  of  the 
manufacturer  to  pay  this  charge,  if  only  for  the  sake 
of  the  improvement  in  the  weaving,  and  for  the 
greater  production  which  can  be  obtained  from 
the  looms  where  a  small  quantity  of  chloride  of 
magnesium  is  present  in  the  size. 

Many  attempts  have  been  made  to  lessen  the  cost 
of  a  size  mixing  by  substituting  chloride  of  magnesium 
for  tallow.  Although  chloride  of  magnesium  has  the 
power  of  softening  the  yarn,  it  can  never  be  entirely 
used  as  a  substitute  for  tallow  or  other  oils.  Up  to  a 
certain  point  it  is  an  ideal  softener,  but  if  a  great 
excess  be  used  the  yarn  will  become  too  damp,  and 


224      The  Chemistry  a,7id  Practice  of  Sizing. 

quite  unfit  for  weaving.  There  is  also  the  danger 
of  iron-stains  being  produced  if  the  amount  of 
tallow  in  the  size  be  reduced  below  a  certain 
proportion.  These  iron  -  stains  are  caused 
through  the  meta!  parts  of  the  looms  rusting 
where  the  yarn  comes  in  contact  with  them. 
For  a  time  no  trouble  will  arise,  then  iron-stains 
will  begin  to  appear,  and  run  through  the 
weaving  shed  like  an  epidemic.  The  writer  has 
been  consulted  in  many  cases  where  iron-stains  have 
developed  in  a  weaving  shed,  and  where  for  months 
there  has  been  no  trace  of  this  trouble.  The  tale 
is  nearly  always  the  same,  i.e.,  "that  no  change  has 
been  made  in  the  mixing,  and  that  the  same  thing 
has  occurred  before,  but  disappeared  again  without 
any  apparent  cause."  In  all  such  cases  the  size 
mixing  in  use  is  just  on  the  danger  point.  If 
at  any  time  there  is  an  extra  quantity  of  condensation 
of  steam  in  the  weaving  shed  at"  night,  the  moisture 
is  attracted  by  the  chloride  of  magnesium  in  the 
yarn,  and  deposited  on  the  looms.  The  small  pro- 
portion of  tallow  present  in  the  size  is  not  sufficient 
to  protect  the  iron-work  from  rusting,  and  next 
morning  the  cloth  will  be  found  iron-stained,  particu- 
larly in  the  reed,  and  on  the  back  rest,  and  temple  bar. 
This  matter  is  further  discussed  under  iron-stains. 

Chloride  of  magnesium  should  never  be  used  as 
an  ingredient  of  size  unless  some  antiseptic,  such  as 
chloride  of  zinc,  is  used  with  it.    The  authors  know 


Chloride  of  Magnesium  in  "Pure*  Size.  225 

of  many  cases  where  mildew  has  developed  in  pure 
sized  cloth,  and  this  has  been  caused  by  a  small 
quantity  of  chloride  of  magnesium  having  got  into 
the  size  accidently.  Generally  it  has  occurred 
through  using  the  same  mixing  beck  for  "pure"  and 
heavy  size  mixings.  Instead  of  cleaning  out  the  beck 
thoroughly,  a  "pure"  mixing  has  been  made  on  the 
top  of  the  remains  of  a  heavier  mixing  which  has  con- 
tained chloride  of  magnesium.  It  is  a  very  common 
practice,  when  changing  a  mixing,  to  run  off  the 
size  from  the  beck  as  far  as  the  tap  at  the  bottom 
will  allow,  and  then  make  a  mixing  of  another 
character  on  the  top  of  what  is  left.  The  manufacturer 
does  not  consider  that  he  is  running  any  risk  by 
so  doing. 

As  a  matter  of  fact  "pure"  sized  cloth  will 
mildew  more  readily  than  heavily  sized  cloth  if 
it  becomes  slightly  damp,  because,  as  a  rule,  it 
does  not  contain  any  antiseptic  substance  to  prevent 
mildew,  whereas  heavily  sized  cloth  invariably  con- 
tains chloride  of  zinc.  This  is  usually  taken  into 
consideration  in  the  taping,  as  it  is  well  known  that 
"pure"  sized  yarns  must  be  more  thoroughly  dried 
than  heavily  sized  yarns. 

The  practice  of  making  a  "pure"  mixing  on  the 
remnants  of  one  containing  chloride  of  magnesium 
also  gives  rise  to  a  damage  previously  mentioned; 
i.e.  tendering  during  the  singeing  operation  in  bleach- 
ing.   The  first  mixing  in  such  a  case  may  contain 

o 


226      The  Chemistry  and  Practice  of  Sizing. 

sufficient  chloride  of  magnesium  to  cause  most 
serious  damage,  especially  if  the  sow  box  has  not 
been  well  cleaned  out,  and  the  flannel  covered 
roller  not  well  washed.  It  looks  a  small  matter  to 
neglect,  and  manufacturers  are  surprised  when  they 
learn  that  tendering  has  occurred  after  the  cloth  has 
been  singed.  This  matter  is  sufficiently  important 
that  if  it  be  found  impossible  to  thoroughly  clean  out 
a  size  beck  for  "pure"  mixings,  a  separate  beck 
should  be  used,  and  kept  for  that  purpose  only. 

Chloride  of  magnesium,  used  in  the  form  of  a 
strong  solution,  has  the  power  of  converting  starch 
into  a  very  adhesive  mass  on  boiling.  This  effect  is 
also  produced  when  a  strong  solution  of  chloride  of 
zinc,  orastrong  solution  of  chloride  of  calcium  is  boiled 
with  starch.  Many  sizing  compounds  have  been  placed 
upon  the  market  which  consist  of  farina  boiled  with 
one  or  other  of  the  foregoing  substances.  They 
have  a  certain  merit,  but  it  might  pay  the  sizer 
to  manufacture  them  himself.  The  additional 
adhesiveness  given  to  starch  by  boiling  with  strong 
solutions  of  the  foregoing  substances  is  not 
obtained  if  very  dilute  solutions  are  boiled  with 
the  starch. 

CHLORIDE  OF  CALCIUM. 

Chloride  of  calcium  is  occasionally  used  in  sizing. 
It  is  a  bye-product  produced  in  many  chemical 
works,  especially  in  bleaching  powder  works  where 


Chloride  of  Calcium. 


227 


chlorinated  lime  is  produced  by  the  Weldon's  pro- 
cess. It  may  also  be  manufactured  by  neutralising 
hydrochloric  acid  with  carbonate  of  calcium  (ordinary 
chalk  or  limestone). 

Chloride  of  calcium  manufactured  by  either  of 
the  above  methods  generally  contains  impurities, 
such  as  salts  of  iron,  free  acid,  and  not  infrequently, 
when  manufactured  by  the  Weldon's  process, 
hypochlorite  of  calcium.  Unless  these  substances 
are  removed  they  may  cause  serious  damage. 

Chloride  of  calcium  must  not  be  used  as  a  softener 
in  conjunction  with  any  of  the  sulphates,  such  as 
Epsom  or  Glaubers  salts.  As  previously  stated, 
on  page  161,  these  substances  undergo  decomposition 
when  they  come  in  contact  with  chloride  of  calcium. 

Chloride  of  calcium  is  not  so  readily  decomposed 
on  heating  as  chloride  of  magnesium.  It  might  on 
this  account  be  used,  with  less  fear  of  damage,  for 
goods  intended  for  bleaching.  At  the  same  time 
it  is  advisable  to  keep  it  out  of  any  mixing  where 
it  is  known  the  cloth  has  afterwards  to  be  bleached. 

Chloride  of  calcium  should  never  be  used  in 
sizing  without  being  systematically  analysed  for  the 
impurities  previously  mentioned.  The  following 
tests  should  be  applied  to  every  consignment 
obtained  from  the  dealers  : — 

Free  Acid. — The  sample  should  be  tested 
for  free  acid  by  means  of  blue  litmus  paper, 
as  described  on  page  34.      If  acid  be  shown  to 


228      The  Chemistry  and  Practice  of  Sizing. 

be  present  it  should  on  no  account  be  used,  as  it 
might  not  only  spoil  the  mixing  by  converting  the 
starchy  matter  into  dextrin  during  the  boiling 
operation,  but  it  might  also  give  rise  to  iron-stains 
when  the  yarn  reached  the  looms.  If  a  large 
quantity  of  the  starchy  matter  became  converted  into 
dextrin,  in  a  heavy  mixing,  it  would  be  impossbile 
to  get  the  right  weight  of  size  on  the  yarn,  as  the 
size  would  dust  off  in  the  process  of  weaving,  and 
probably  cause  "soft  beams." 

Chloride  of  Iron. — The  sample  should  be 
carefully  tested  for  iron  by  means  of  a  solution  of 
ferrocyanide  of  potassium.  If  a  blue  colour  be 
produced  it  should  not  be  used  unless  passed  as 
safe  by  an  expert,  and  if  a  blue  precipitate  be 
produced  on  the  addition  of  the  ferrocyanide  of 
potassium,  it  should  be  rejected  without  hesitation, 
as  such  a  sample — and  many  such  are  sold  to  sizers — 
would  most  certainly  give  rise  to  iron-stains  in  the 
woven  cloth. 

Hypochlorite  of  Calcium. — Hypochlorite  of 
calcium  has  been  found  in  many  samples  of  chloride 
of  calcium  sold  to  sizers.  It  is  a  most  dangerous 
impurity,  for  although  it  may  be  successfully 
employed  in  converting  starch  into  a  soluble  form  of 
starch,  if  rightly  used,  it  may,  if  its  presence  be  not 
known,  cause  serious  damage  by  thinning  the  size  to 
such  an  extent  as  to  cause  "soft  beams."  In  mixing 
heavy  size  it  is  usual  to  boil  the  chloride  of  calcium 


Glycerin. 


229 


along  with  the  China  clay  in  an  iron  pan.  If  hypo- 
chlorite of  calcium  be  present  it  will  attack  the  iron, 
and  sufficient  may  be  brought  into  solution  to  cause 
iron-stains.  Such  a  case  came  under  the  writer's 
notice  some  time  ago.  In  this  case  the  solution 
of  chloride  of  calcium  was  so  charged  with  hypo- 
chlorite of  calcium  that  free  chlorine  was  given  off 
when  it  was  boiled  with  the  clay.  The  iron  of  the 
pan  was  attacked  to  such  an  extent  that  the  clay 
was  coloured  brown.  Had  this  gone  into  the 
mixing  unnoticed  the  cloth  sized  with  it  would 
have  been  spoiled. 

The  presence  of  hypochlorite  of  calcium  may  be 
detected  by  adding  a  few  drops  of  dilute  hydro- 
chloric acid  to  the  solution,  in  a  test  tube,  and  gently 
warming.  No  odour  of  chlorine  should  be  shown 
by  this  test.  If  chlorine  be  shown  to  be  present,  the 
sample  should  not  be  used.  A  further  test  might 
be  made  by  adding  a  small  quantity  of  a  solution  of 
iodide  of  potassium  to  the  suspected  solution,  and 
afterwards  a  small  quantity  of  thin  starch  paste. 
If  chlorine  be  liberated  on  the  addition  of  very  dilute 
acid,  it  will  decompose  the  iodide  of  potassium, 
liberating  free  iodine.  This  latter  substance,  in 
contact  with  the  starch,  will  show  a  deep  blue  colour. 

GLYCERIN. 

Glycerin  is  produced  in  large  quantities  in  the 
operation  of  manufacturing  soap.     At  one  time  it 


230      The  Chemistry  and  Practice  of  Sizing . 


was  considered  a  waste  product,  and  was  thrown 
away  with  the  spent  lye.  To-day  it  is  of  more  value 
than  the  soap  itself.  Glycerin  is  also  manufactured 
by  passing  super-heated  steam  through  oils  and  fats, 
and  by  this  method  large  quantities  of  glycerin  are 
now  obtained. 

Pure  glycerin  should  have  a  specific  gravity  of 
1*261,  and  it  should  not  leave  any  ash  when  burnt 
in  a  platinum  crucible  over  the  Bunsen's  flame. 
The  absence  of  ash  shows  the  absence  of  mineral 
impurities,  or  mineral  adulterants. 

Crude  commercial  glycerin,  as  sold  for  sizing 
purposes,  generally  contains  80  per  cent  of  real 
glycerin,  10  per  cent,  of  mineral  matter  (the  chief 
portion  of  which  is  common  salt),  and  10  per 
cent,  of  water  and  organic  matter.  Commercial 
glycerin  containing  80  per  cent,  of  real  glycerin  is 
suitable  for  sizing  purposes. 

Glycerin  is  frequently  adulterated  with  chloride 
of  magnesium,  chloride  of  calcium,  and  glucose.  It 
should,  therefore,  be  always  tested  for  these 
substances.    The  tests  may  be  made  as  follows:  — 

Percentage  of  Asii. — This  is  determined  by 
burning  a  weighed  portion  of  glycerin  in  a  platinum 
crucible,  and  weighing  the  resultant  ash.  If  free 
from  ash,  mineral  adulterants  cannot  be  present. 
The  burning  should  be  conducted  at  as  low  a  tem- 
perature as  possible,  otherwise  chloride  of  sodium, 
if  present,  will  be  partially  volatilised.     If  glucose 


Glycerin — Adulterants  of. 


231 


be  present  it  may  be  detected  during  the  burning 
process  by  the  characteristic  smell  of  burnt  sugar, 
and  by  the  amount  of  carbonisation  which  takes 
place. 

Calcium  and  Magnesium. — A  few  drops  of 
ammonia,  and  an  excess  of  chloride  of  ammonium 
should  be  added  to  a  solution  of  the  glycerin,  and 
afterwards  a  solution  of  oxalate  of  ammonium. 
A  white  precipitate  is  formed  if  calcium  be  present 
and  no  precipitate  is  formed  if  the  sample  be 
free  from  calcium.  If  calcium  be  found,  an 
excess  of  oxalate  of  ammonium  must  be  added  to 
precipitate  the  whole  of  it,  and  the  liquid  filtered. 
The  filtrate  is  tested  for  magnesium  by  adding  an 
excess  of  solution  of  ammonia  and  a  solution 
of  phosphate  of  ammonium.  A  white  granular 
precipitate  is  formed  if  magnesium  be  present. 
Another  portion  of  the  glycerin  should  be  dissolved 
in  distilled  water  and  tested  for  hydrochloric  acid 
(chlorides)  by  adding  a  few  drops  of  nitric  acid  and 
nitrate  of  silver.  A  white  curdy  precipitate  is 
produced  if  chlorides  be  present.  (Crude  glycerin 
will  always  show  the  presence  of  chlorides,  on 
account  of  the  chloride  of  sodium  which  is  in- 
variably present,  but  pure  glycerin  should  be  free). 

Glucose. — Glucose  may  be  detected  in  glycerin 
by  boiling  a  portion  with  Fehling  s  solution.  A  red 
precipitate  of  cuprous  oxide  is  formed  if  glucose  be 
present.    This  test  must  be  made  with  care  as 


232       The  Chemistry  and  Practice  of  Sizing. 


glycerin  will  decompose  Fehling's  solution  if  the 
boiling  is  prolonged.  Crude  commercial  glycerin 
always  shows  the  reaction  for  glucose. 

Crude  commercial  glycerin  has  a  specific  gravity 
of  about  1*30,  and  it  should  be  free  from  glucose  and 
the  chlorides  of  calcium  and  magnesium. 

Use  of  Glycerin  in  Sizing. 

Glycerin  is  a  very  hygroscopic  substance,  and 
on  this  account  may  be  used  to  advantage  in  "pure" 
sizing  for  the  purpose  of  improving  the  weaving. 
This  is  especially  so  where  the  goods  have  to  be 
bleached.  It  possesses  none  of  the  objectionable 
features  of  chloride  of  magnesium  or  chloride  of 
calcium.  The  chief  objection  to  its  use  is  its  high 
price.  Ifglycerin  be  used  in  "pure"  sizing,  for  goods 
which  are  intended  to  be  sold  in  the  grey  state,  it 
will  be  advisable  to  use  a  little  salicylic  acid  in  the 
mixing.  This  will  prevent  the  formation  of  mildew, 
a  danger  to  be  feared  wherever  deliquescent  sub- 
stances are  used  in  "pure"  sizing.  This  matter  is 
further  discussed  under  salicylic  acid. 

GLYCERIN  SUBSTITUTES. 

Substances  are  often  sold  as  "glycerin  substi- 
tutes" or  "glycerin  softeners"  to  manufacturers. 
They  rarely  contain  any  glycerin  at  all,  being 
generally  mixtures  of  chloride  of  magnesium, 
glucose,  and  water,  or  chloride  of  calcium,  glucose 


Glycerin  Substitutes, 


and  water,  and  sometimes  mixtures  containing  equal 
volumes  of  chloride  of  zinc  and  chloride  of  mao- 
nesium.  They  are  possibly  useful,  but  the  price 
charged  for  them  is  very  much  higher  than  the  actual 
value  of  the  components  of  the  mixture. 

The  following  analyses  give  the  composition  of 
three  of  these  glycerin  substitutes: — 


No.  I 

No.  2 

No.  3 

per  cent 

.   per  cent. 

per  cent. 

Chloride  of  Magnesium 

..     30  .. 

.     40  ... 

14*02 

Chloride  of  Zinc 

2576 

Glucose   

•    4"S  •• 

.     4-0  ... 

Water   

.  92-5  .. 

.  92*0  ... 

6o'22 

IOO'O 

IOO'O 

IOO'OO 

The  glycerin  substitute  marked  No.  3  was  sold 
by  the  dealer  at  12/6  per  cwt.  Its  value  was  under 
5/-  per  cwt.  The  writer  has  come  across  cases 
where  as  much  as  25/-  per  cwt.  has  been  charged 
for  a  similar  preparation.  It  could  have  been  made 
by  the  manufacturer  by  mixing  together  equal 
volumes  of  chloride  of  zinc  solution  at  102°  T.  and 
chloride  of  magnesium  solution  at  56°  T. 

GLUCOSE. 

This  substance  is  sometimes  used  for  sizing,  but 
more  often  for  "finishing"  cotton  goods.  It  is  hardly 
a  "softener"  in  the  true  sense,  as  it  may  also  be 
employed  to  give  a  hard  feel  to  cloth  or  yarn.  Its 
effect  may  be  varied  according  to  the  manner  in 


234       The  Chemistry  and  Practice  of  Sizing. 


which  it  is  dried  on  the  yarns,  and  according  to  the 
presence  or  absence  of  deliquescent  substances  in 
the  size. 

Glucose  sugar  is  largely  produced  on  the 
Continent  and  in  America  from  starch.  Chemically 
it  is  the  same  as  the  sugar  found  in  grapes.  The 
American  glucose  is  manufactured  almost  entirely 
from  maize  starch,  that  on  the  Continent  from 
farina.  The  process  consists  in  boiling  the  starch 
with  water  and  sulphuric  acid,  using  about  2  per 
cent,  of  acid.  This  acid  is  finally  neutralised  with 
lime  or  chalk,  which  combines  with  the  acid  to  form 
insoluble  sulphate  of  calcium.  The  sugar  liquor  is 
separated,  filtered,  and  afterwards  evaporated  in 
vacuo  to  a  certain  consistency  to  be  sold  as  liquid 
glucose,  or  still  further  evaporated  until  it  solidifies, 
when  it  is  sold  as  glucose  chips. 

Glucose  is  more  often  used  in  sizing  in  the 
form  of  glycerin  substitutes,  than  simply  as  glucose. 
It  is  a  suitable  medium  for  mildew  development, 
and  it  has  no  special  properties  which  make  it 
valuable  for  sizing,  although  it  has  valuable  proper- 
ties as  an  ingredient  for  "finishing." 


Chloride  of  Zinc. 
Chapter  VI. 


235 


Ingredients  used  for  preserving  Size 
from  Mildew. 

IT  is  necessary  to  use  some  substance  for  preserv- 
ing size  from  mildew  in  all  cases  where 
deliquescent  chemicals  have  been  used  as  softening 
agents.  No  cloth  is  safe  from  mildew  which  con- 
tains such  ingredients  as  chloride  of  magnesium  or 
chloride  of  calcium,  unless  an  antiseptic  is  used  at 
the  same  time. 

CHLORIDE  OF  ZINC. 

Chloride  of  zinc  is  the  most  important  antiseptic 
used  in  sizing  cotton  yarns.  It  is  a  compound  of 
chlorine  and  zinc,  and  is  prepared  in  several  ways. 
The  method  generally  employed  is  to  dissolve  zinc 
in  hydrochloric  acid.  The  solution  takes  place  with 
a  violent  re-action,  and  large  quantities  of  hydrogen 
gas  are  given  off.  The  zinc  very  often  contains 
arsenium  as  an  impurity,  and  when  this  is  the  case, 
arseniuretted  hydrogen  is  liberated  along  with  the 
hydrogen.      Arseniuretted  hydrogen  is  one  of  the 


236      The  Chemistry  and  Practice  of  Sizing. 

most  powerful  poisons  known,  and  great  care  should 
be  taken  that  the  gaseous  products  are  carried  away 
from  persons  employed  in  the  manufacture  of 
chloride  of  zinc. 

Chloride  of  zinc  is  also  prepared  from  "calamine," 
a  native  carbonate  of  zinc.  Hydrochloric  acid  is 
used  as  before,  and  carbonic  acid  gas  (carbon 
dioxide),  is  given  off. 

When  metallic  zinc  is  used,  it  is  generally  in  the 
form  of  spelter,  or  in  the  form  of  scrap  zinc,  collected 
from  many  sources.  All  forms  of  zinc  contain 
numerous  impurities.  The  most  objectionable  one 
from  a  sizer's  point  of  view  is  iron.  This  metal  is 
dissolved  in  the  acid  at  the  same  time  as  the  zinc, 
and  remains  in  solution  in  the  form  of  chloride  of 
iron.  It  is  absolutely  necessary  to  remove  this 
impurity  from  chloride  of  zinc,  and  if  carefully 
manufactured,  it  can  be  obtained  quite  free  from  it. 
If  chloride  of  iron  be  not  removed,  it  will  discolour 
the  cloth  by  producing  iron-stains. 

The  following  is  the  usual  method  of  removing 
iron  salts  from  a  solution  of  chloride  of  zinc: — Chlorine 
may  be  passed  into  the  solution  or  it  may  be  treated 
with  chlorinated  lime  or  chlorate  of  potash.  These 
substances  convert  the  iron  from  the  ferrous  to  the 
ferric  state.  This  operation  is  necessary  because 
ferrous  iron  is  not  completely  precipitated  in  the  next 
stage,  whereas  ferric  iron  is  completely  precipitated. 
After  adding  one  or  other  of  the  above  oxidising 


Chloride  of  Zinc — Preparation  of,  237 


agents,  lime,  or  better,  "calamine"  (the  impure 
hydrato-carbonate  of  zinc  previously  mentioned)  is 
added.  This  precipitates  the  ferric  iron  as  ferric 
hydrate.  The  following  equations  will  illustrate  the 
re-action : — 

2FeCL        +       CL        =  Fe2Cl6 

Soluble  Ferrous  Chloride  Soluble  Ferric  Chloride, 

in  the  chloride  of  zinc. 

Fe2Cl6     +         3ZnH,0.,      =    Fe26H0    +  3ZnCl2 

Ferric  Chloride.     "Calamine" — Hydrate        Insoluble  Chloride  of 

of  Zinc.  Ferric  Hydrate  Zinc, 

precipitated. 

Not  the  least  of  the  advantages  to  be  obtained 
from  the  use  of  " calamine,"  or  lime,  for  the  purpose  of 
precipitating  iron  salts  is  that  these  substances  have 
the  effect  of  neutralising  any  trace  of  free  acid  which 
may  have  been  left  in  the  chloride  of  zinc  solution. 
The  presence  of  small  quantitiesof  chloride  of  calcium 
in  the  finished  product  is  due  to  the  use  of  lime  as  the 
precipitating  agent,  and  this  must  not  be  confused 
with  chloride  of  calcium  which  may  have  been  added 
as  an  adulterant. 

Sometimes  oxidation  is  allowed  to  take  place  by 
exposing  the  impure  chloride  of  zinc  to  the  atmos- 
phere for  a  long  period,  but  the  method  is  slow  and 
requires  great  storage. 

After  the  chloride  of  zinc  has  been  treated  as 
above  it  is  allowed  to  stand  and  settle.  The  clear 
solution  is  run  off  from  the  deposited  iron  precipi- 
tate, and,  where  necessary,  this  is  evaporated  down  to 
a  specific  gravity  varying  from  1*46  to  1*52  or  92°  to 


238      The  Chemistry  and  Practice  of  Sizing'. 

1 04°  Twaddell,  in  which  form  it  is  usually  sold  in 
this  country.  For  shipment  abroad  it  is  further 
evaporated  until  it  solidifies.  In  this  state  it  costs 
less  for  freight  charges,  because  the  payment  of 
carriage  on  water  is  avoided. 

With  the  exception  of  tallow  and  soap,  chloride 
of  zinc  is  one  of  the  most  expensive  of  the  ordinary 
ingredients  of  size.  As  previously  stated,  it  is 
generally  sold  in  solution  in  this  country.  The 
liquid  is  more  convenient  to  handle  than  the  solid, 
but  it  lends  itself  more  open  to  adulteration. 
The  consequences  of  adulteration  may  be  far 
more  serious  with  this  substance  than  with  any  of 
the  others.  Within  the  writer's  own  knowledge, 
many  cases  of  mildew  have  been  caused  by 
using  adulterated  chloride  of  zinc.  A  peculiar  case 
of  adulteration  came  under  notice  a  few  years  ago.  A 
certain  firm  had  been  in  the  habit  of  buying  chloride 
of  zinc  from  one  agent  only  for  many  years,  for  which 
they  paid  a  very  high  price.  On  one  occasion 
they  ran  short,  and  sent  for  a  quantity  from  Messrs. 
Wm.  Blythe  &  Co.  Ltd.,  of  Church,  to  put  them  on 
until  they  could  get  a  consignment  from  their  usual 
dealer.  This  was  invoiced  at  £2  per  ton  less  than 
they  had  been  in  the  habit  of  paying.  After  using  a 
considerable  portion  of  the  chloride  of  zinc  from  one 
cask  it  was  found  that  the  sized  warps  were 
different  in  "feel"  than  formerly.  With  a  view 
to  discover  the  cause  of  this  the  zinc  was  submitted 


Adulteration  of  Chloride  of  Zinc.  239 

to  analysis,  and  was  found  to  be  pure  and  of 
good  quality.  In  questioning  the  manufacturer 
the  writer  found  that  he  was  using  more  than  double 
the  quantity  of  chloride  of  zinc  necessary  to  keep 
the  size  from  developing  mildew.  This  quantity 
was  the  quantity  laid  down  by  the  agent  who  had 
supplied  them  in  the  first  instance.  This  being  the 
case,  the  writer  suggested  making  an  analysis  of  a 
sample  of  the  chlorideof  zinc  they  had  been  previously 
using.  It  was  found  to  be  grossly  adulterated  with 
common  salt,  and  instead  of  containing  from  44  to  46 
per  cent,  of  chloride  of  zinc,  it  contained  only  14  per 
cent.,  and  33  per  cent,  of  common  salt.  The  cause 
of  the  difference  in  the  feel  of  the  yarns  where  a  pure 
chloride  of  zinc  was  used  was  accounted  for  at  once. 
In  using  the  same  quantity  of  the  pure  article  they 
had  been  using  a  very  large  excess.  It  is  a  well- 
known  fact  than  an  excessive  quantity  of  chloride  of 
zinc  does  not  improve  the  weaving. 

The  following  substances  are  often  found  in 
commercial  chloride  of  zinc,  either  as  impurities  or 
as  adulterations  : — 

(1)  Chloride  of  Sodium  (common  salt). 

(2)  Chloride  of  Iron. 

(3)  Chloride  of  Calcium. 

(4)  Chloride  of  Magnesium. 

(5)  Chloride  of  Ammonium. 

(6)  Sulphate  of  Soda  (Glauber's  salts). 

In  making  the  necessary  tests,  the  following 
method  of  procedure  should  be  followed  : — 


240      The  Chemistry  and  Practice  of  Sizing. 

(1)  The  specific  gravity  should  be  taken  as 
described  on  pages  26  and  27,  either  by  means  of 
the  specific  gravity  bottle  or  by  means  of  a  suitable 
Twaddell's  hydrometer. 

The  specific  gravity  test  is  useful  but  it  is  not 
sufficient  to  determine  the  purity  of  a  sample  of 
chloride  of  zinc.  Two  liquids,  supposed  to  be 
chloride  of  zinc,  may  have  the  same  specific  gravity, 
or  Twaddell,  and  one  may  be  pure  and  the  other 
impure.  As  a  general  rule,  however,  if  it  be 
found  that  the  sample  under  examination  is  free 
from  more  than  traces  of  impurities,  and  the  specific 
gravity  is  high,  it  may  be  passed  as  pure,  because  it 
is  impossible  to  get  a  high  specific  gravity  with  any 
substance  likely  to  be  used  as  an  adulterant. 

(2)  Common  Salt. — This  substance  is  always 
found  in  chloride  of  zinc  in  greater  or  smaller 
quantities.  The  usual  test  for  the  presence  of  a 
sodium  salt  is  made  by  means  of  the  Bunsen's 
flame.  A  perfectly  clean  piece  of  platinum  wire  is 
dipped  into  hydrochloric  acid  and  heated  in  the  top 
part  of  the  Bunsen's  flame,  until  it  ceases  to  give  a 
yellow  colour  when  placed  at  the  edge  of  the  lower 
part  of  the  flame.  The  clean  wire  is  then  dipped 
into  the  chloride  of  zinc  solution,  or  other  substance 
to  be  tested,  and  the  drop  at  the  end  of  the  wire  is 
introduced  into  the  flame.  Sodium  salts  give  an 
intensely  yellow  tint  to  a  Bunsen's  flame.  This 
test,  however,  is  no  use  at  all  for  such  a  commercial 


Chloride  of  Sodium  in  Chloride  of  Zinc,  241 

article  as  chloride  of  zinc,  because  traces  of  most 

impurities  may  be  ignored  unless  they  be  of  an 

injurious  nature.     The  best  test  for  the  presence  of 

common  salt  as  an  adulterant  is  the  following,  and 

should  be  conducted  in  a  long  narrow  test  tube:— 

The  test  tube  is  filled  one-third  full  with  the  solution 

of  chloride  of  zinc.    To  this  is  added  twice  its  bulk 

of  strong  hydrochloric  acid,  and  the  mixture  well 

shaken  up.     If  there  be  any  excess  of  common  salt,  it 

will  be  precipitated  on  standing  a  few  seconds.  The 

salt  may  be  filtered  off  and  the  hydrochloric  acid 

removed  by  drying. 

No  adulterated  samples  of  chloride  of  zinc  would 

contain  less  than  1  per  cent,  of  common  salt,  for  the 

simple  reason  that  it  does  not  pay  to  adulterate  in 

traces.    The  great  value  of  this  test  is,  that  it  passes 

over  mere  traces,  and  precipitates  only  quantities 

which  have  been  added  for  purposes  of  adulteration. 

In  all  cases  a  sample  of  chloride  of  zinc  should  be 

condemned  if  salt    be  precipitated    by  this  test. 

Another  advantage  of  this  test  is,  that  the  common 

salt  is  precipitated  exactly  in  the  same  form  as  it 

was  added  to  the  chloride  of  zinc,   no  chemical 

change  having  taken  place.     It  is  possible,  therefore, 

to  confront  the  dealer  with  the  actual  evidence  of 

his  fraud.    The  test  depends  upon  the  fact  that 

common  salt  is    only  slightly    soluble    in  strong 

hydrochloric  acid,   although  it  is  very  soluble  in 

water, 
p 


242      The  Chemistry  and  Practice  of  Sizing. 

(3)  Chloride  of  Calcium. — This  substance  is 
often  found  in  small  quantities  in  chloride  of  zinc, 
and  its  presence  is  generally  due  to  the  use  of  lime 
and  chlorinated  lime  for  the  purpose  of  oxidising 
and  precipitating  the  iron  salts.  It  is  also  very 
often  used  as  an  adulterant, 

Where  chloride  of  calcium  is  present  in  such 
quantities  as  to  warrant  the  assumption  that  it  has 
been  wilfully  added  to  increase  the  profits  of  the 
seller  it  is  very  objectionable.  It  lessens  the  amount 
of  actual  chloride  of  zinc  present  in  the  solution  and 
it  is  entirely  opposite  in  its  action.  It  has  no  anti- 
septic properties,  but,  on  the  contrary,  it  has  a  strong 
tendency  to  assist  in  the  development  of  mildew 
growths  on  account  of  its  power  of  absorbing 
moisture.  It  may  also  alter  the  character  of  the 
size  if  any  of  the  sulphates,  such  as  Glaubers  or 
Epsom  salts,  are  present  in  the  mixing.  The 
following  is  the  best  method  of  testing  for  the 
presence  of  chloride  of  calcium  : — 

A  small  portion  of  the  sample  is  placed  in  a  large 
test  tube,  and  twice  its  bulk  of  water,  and  a  little 
ammonium  chloride  solution  added.  Strong  ammonia 
is  then  added  drop  by  drop  until  the  precipitate  of 
hydrate  of  zinc  first  formed  is  dissolved.  A  solution 
of  oxalate  of  ammonium  is  then  added.  The 
presence  of  calcium  is  shown  by  the  formation  of  a 
white  precipitate.  If  a  slight  cloudiness  be  pro- 
duced, only  a  small  trace  of  calcium  can  be  present. 


Chloride  of  Zinc — Impurities  in.  243 


If  the  precipitate  is  bulky  and  quickly  settles,  it  is 
probable  that  there  is  adulteration.  In  such  a 
case  the  sample  should  be  submitted  to  a  trained 
analyst  to  determine  the  amount. 

An  important  confirmatory  test  for  the  presence 
of  calcium  salts  is  to  dip  a  clean  platinum  wire  in 
hydrochloric  acid,  and  take  up  a  portion  of  the 
precipitate  on  the  end  of  the  moistened  wire.  This 
is  introduced  into  the  Bunsen's  flame  as  in  the 
sodium  test.  Calcium  salts  give  a  brick-red  colour- 
ation to  the  flame  not  easily  mistaken. 

(4)  Chloride  of  Magnesium. — This  salt  is  very 
often  found  in  chloride  of  zinc,  generally  in  small 
quantities  as  an  impurity,  but  sometimes  in  large 
quantities  as  an  adulterant.  The  filtrate  from  the 
precipitated  oxalate  of  calcium  in  the  previous  test  is 
examined  for  magnesium  by  adding  a  solution  of 
ammonia  and  a  solution  of  phosphate  of  sodium.  A 
white  granular  precipitate  will  be  at  once  formed  if 
magnesium  salts  are  present.  No  notice  should  be 
taken  of  a  precipitate  which  forms  on  standing  some 
time.  This  latter  precipitate  is  from  the  zinc 
itself.  In  accurate  work  it  is  necessary  to  remove 
the  zinc  before  testing  for  either  calcium  or 
magnesium. 

(5)  Test  for  Sulphates. — The  presence  of  such 
salts  as  magnesium  and  sodium  sulphates  may  be 
detected  by  adding  water  and  hydrochloric  acid  to 
the  solution  of  chloride  of  zinc  contained  in  a  test 


244       The  Chemistry  and  Practice  of  Sizing. 


tube,  and,  after  shaking  up,  a  few  drops  of  barium 
chloride  solution.  A  heavy  white  precipitate  is 
formed  if  sulphates  be  present. 

In  this  test  care  should  be  taken  not  to  add  too 
much  strong  hydrochloric  acid,  as  this  substance  pre- 
cipitates chloride  of  barium  from  solution,  just  as  in 
the  case  of  common  salt.  The  precipitate  if  formed, 
however,  is  soluble  in  excess  of  water,  and  is  readily 
distinguished  by  this  means  from  the  sulphate  of 
barium.  If  there  be  a  heavy  precipitate  of  sulphate 
of  barium,  it  may  be  that  there  are  both  magnesium 
and  sodium  sulphates  present.  If,  in  the  previous 
tests,  magnesium  salts  were  shown  to  be 
absent,  then  the  sulphate  will  be  sulphate  of 
sodium  only. 

(6)  Chloride  of  Ammonium. — This  substance 
is  almost  invariably  present  in  chloride  of  zinc  as  an 
impurity.  It  is  easily  detected  by  adding  a  small 
quantity  of  the  zinc  solution  to  an  excess  of  solution 
of  caustic  soda  in  a  test  tube,  and  gently  boiling. 
Ammonia,  in  the  form  of  gas,  will  be  driven  off,  and 
may  be  recognised  by  the  characteristic  smell  of  that 
substance.  Traces  may  be  detected  by  holding  a 
piece  of  wet  red  litmus  paper  at  the  mouth  of  the 
test  tube,  taking  care  that  the  liquid  in  the  tube 
does  not  touch  it.  The  litmus  paper  is  turned  blue 
if  ammonia  be  present.  Chloride  of  ammonium  is 
never  wilfully  used  as  an  adulterant  in  chloride  of 
zinc  on  account  of  its  high  price. 


Chloride  of  Zinc — Impurities  in.  245 


Objectionable  Impurities. 
Under  this  heading  will  be  described  those 
impurities  which  are  due  either  to  the  zinc  or  to  the 
acid  from  which  the  chloride  of  zinc  is  prepared, 
or  to  a  faulty  method  of  manufacture.  These  im- 
purities are  in  no  sense  adulterants,  their  presence 
being  purely  accidental.  Notwithstanding  this,  if 
they  be  present,  they  will  cause  serious  damage  to 
the  cloth. 

(1)  Iron  Salts. — The  presence  of  iron  salts  is 
objectionable  in  all  substances  used  for  sizing.  The 
tests  for  iron  are  so  delicate,  however,  that  they  are 
often  misleading  unless  carried  out  by  an  expert. 

In  testing  chloride  of  zinc  for  iron  the  solution 
should  be  treated  as  follows  : — A  sample  is  placed 
in  a  large  test  glass,  or  beaker,  and  exposed 
to  the  air  for  a  few  days,  care  being  taken  to  avoid 
contamination  with  dust.  Any  large  quantities  of 
iron,  which  should  have  been  removed  before  the 
zinc  was  put  on  the  market,  will  be  shown  by  the 
formation  of  a  brownish  red  precipitate.  Chloride  of 
zinc  depositing  iron  in  this  way  should  never  be  used 
for  sizing. 

Where  iron  exists  in  traces  only  it  is  necessary  to 
employ  a  much  more  delicate  test,  and  for  this 
purpose  ferrocyanide  of  potassium,  or  sulphocyanide 
of  potassium,  may  be  used.  Ferrocyanide  of  potas- 
sium gives  a  blue  colouration,  or  a  blue  precipitate, 
according  to  the  amount  of  iron  present,  whilst 


246      The  Chemistry  and  Practice  of  Sizing. 

sulphocyanide  of  potassium  gives  a  blood  red  colour- 
ation with  soluble  ferric  salts  in  the  presence  of 
nitric  acid.  Ferrocyanide  of  potassium  produces  a 
white  precipitate  with  zinc  salts,  and  the  blue 
colour  may  be  masked  if  the  test  be  not  carefully 
performed. 

A  solution  of  logwood  gives  a  pink  colour  with 
pure  cloride  of  zinc  solution,  but  in  the  presence  of 
iron  the  colour  is  changed  to  dark  blue. 

A  good  test  for  the  presence  of  iron  in  chloride 
of  zinc  is  made  by  adding  an  excess  of  ammonia  to 
the  diluted  solution  of  zinc,  and  then  a  solution  of 
sulphide  of  ammonium.  If  the  sample  be  free  from 
iron  a  white,  or  yellowish  white,  precipitate  of 
sulphide  of  zinc  will  be  formed,  but  if  iron  be  present 
the  precipitate  will  be  dark  in  colour.  The  presence 
of  lead  will  also  darken  the  precipitate,  and  this  may 
be  mistaken  for  iron.  If,  therefore,  a  dark  coloured 
precipitate  be  formed,  another  portion  of  the  zinc 
must  be  acidified  with  hydrochloric  acid,  and 
sulphuretted  hydrogen  gas  passed  through  the 
solution.  Lead,  if  present,  is  precipitated,  or  the 
solution  is  darkened  by  this  test.  After  filtering, 
the  solution  should  be  rendered  alkaline  with  a 
solution  of  ammonia.  If  iron  be  present  it  will  be 
precipitated  as  sulphide  in  the  alkaline  solution. 

The  authors  find  that  most  samples  of  chloride 
of  zinc  manufactured  at  the  present  time  are  practic- 
ally free  from  iron.    More  care  is  exercised  in  the 


Chlo7'ide  of  Zinc — Free  Acid  in,  247 


production  of  this  substance  than  was  formerly  the 
case.  Occasionally  a  sample  is  found  containing  an 
outrageous  quantity  of  chloride  of  iron.  One  such 
sample  is  shown  on  page  253.  This  sample  con- 
tained 6*oi  per  cent,  of  chloride  of  iron,  and  when 
boiled  in  contact  with  yarn  in  the  sow-box  of  the 
tape  frame  oxide  of  iron  was  actually  precipitated  in 
sufficient  quantity  to  colour  the  size  red.  A  solution 
such  as  the  fore-going  could  not  fail  to  be  noticed, 
by  anyone  used  to  solutions  of  chloride  of  zinc, 
on  account  of  the  green  tint  always  present 
when  an  excessive  amount  of  chloride  of  iron 
is  present. 

(2)  Free  Acid. — Free  acid  is  another  objection- 
able substance  sometimes  found  in  chloride  of 
zinc.  The  test  for  acid,  by  means  of  litmus  paper, 
requires  carefully  conducting  as  chloride  of  zinc 
itself  will  turn  blue  litmus  paper  red.  In  the  case 
of  chloride  of  zinc  free  from  acid  the  change  is 
gradual,  but  if  the  litmus  paper  becomes  red  at  once 
the  zinc  should  be  rejected.  A  better  test  is  made 
by  adding  a  drop  of  dilute  methyl  orange  solution 
to  a  diluted  solution  of  zinc.  If  acid  be  present  it 
will  be  shown  by  the  production  of  a  pink  colouration. 

The  objection  to  free  hydrochloric  acid  in  such 
substances  as  chloride  of  zinc  has  already  been  dis- 
cussed under  chloride  of  magnesium  and  chloride  of 
calcium  on  pages  222  and  228.  It  may  weaken 
the  size  and  tender  the  cloth,  and  it  is  almost 


248      The  Chemistry  and  Practice  of  Sizing. 


certain  to  produce  iron-stains  where  the  yarn  comes 
into  contact  with  the  iron  of  the  looms. 

(3)  Lead  (Chloride  of  lead). — This  substance 
is  frequently  found  in  chloride  of  zinc.  Its  presence 
may  be  shown  by  passing  sulphuretted  hydrogen 
gas  through  the  acidified  solution,  as  previously 
described.  If  lead  be  present  a  black  or  brownish 
precipitate  will  be  formed.  If  a  trace  only  be 
present  the  liquid  is  discoloured. 

Analysis  of  Chloride  of  Zinc. 

The  value  of  a  sample  of  chloride  of  zinc  to  the 
sizer  is  determined  by  the  amount  of  actual  chloride 
of  zinc  present,  if  objectionable  impurities,  such  as 
acid  or  iron  salts,  are  absent.  Samples  showing  a 
high  specific  gravity  or  Twaddell  are  almost  always 
free  from  adulteration,  but  they  are  not  necessarily 
free  from  injurious  impurities.  As  a  matter  of  fact  it 
is  impossible  to  get  sufficient  of  any  adulterant,  such  as 
the  chlorides  of  calcium,  magnesium,  or  sodium,  into 
solution,  which  will  give  the  necessary  high  specific 
gravity  at  which  chloride  of  zinc  is  usually  sold. 

The  manufacturer  should  know  how  to  determine 
the  amount  of  actual  chloride  of  zinc  present  in  the 
sample  he  is  using.  Two  methods  are  available,  the 
first  by  volumetric  analysis,  and  the  second,  by 
gravimetric  analysis. 

The  following  volumetric  estimation  (Fahlberg 
and  Maxwell  Lyte)  has  been  found  useful  by  the 


Analysis  of  Chloride  of  Zinc, 


249 


authors.  The  method  is  not  available  in  the  presence 
of  iron,  but  as  most  samples  of  chloride  of  zinc  sold 
to  sizers  are  practically  free  from  this  substance  the 
process  may  be  used  nine  times  out  of  ten  without 
any  previous  preparation  of  the  chloride  of  zinc.  If 
iron  be  found  to  be  present  in  the  preliminary  tests 
it  must  be  removed  as  follows  : — 

The  zinc  should  be  acidified  with  hydrochloric 
acid  and  boiled.  Whilst  boiling,  a  little  chlorate  of 
potash  or  strong  nitric  acid  should  be  added  to 
oxidise  any  ferrous  iron  to  the  ferric  state.  The 
solution  is  then  treated  with  ammonia  in  excess,  and 
filtered.  The  filtrate  contains  the  zinc  in  solution  in 
the  excess  of  ammonia.  The  precipitated  ferric 
hydrate  is  washed  with  dilute  ammonia,  and  the 
washings  collected  and  added  to  the  zinc  filtrate.  A 
small  amount  of  zinc  is  always  carried  down  with  the 
ferric  hydrate.  This  precipitate  should  therefore  be 
dissolved  in  hydrochloric  acid,  and  re-precipitated 
with  excess  of  ammonia  as  before,  filtrered,  and  the 
filtrate  collected  in  the  zinc  solution.  To  the  solution 
hydrochloric  acid  is  added  in  excess,  and  brought  to 
the  boiling  point.  This  is  then  titrated  with  standard 
ferrocyanide  of  potassium,  as  described  hereafter, 
using  uranium  nitrate  as  the  indicator. 

Solutions  Required. 
(1)  A    standard    solution    of  ferrocyanide  of 
potassium  of  such  a  strength  that   1  c.c.  =  0*01 
gramme  of  zinc. 


250       The  Chemistry  and  Practice  of  Sizing. 


(2)  A  standard  solution  of  zinc,  made  by 
dissolving  10  grammes  of  pure  metallic  zinc  in 
hydrochloric  acid  and  diluting  to  1  litre  =  (1,000 
cubic  centimeters).  Each  c.c.  of  this  solution  will 
contain  o*oi  gramme  of  zinc. 

(3)  A  solution  of  uranium  nitrate. 

The  Analytical  Process. — A  beaker  is  care- 
fully weighed  on  the  balance  and  about  1  gramme 
of  the  chloride  of  zinc  to  be  estimated  added,  and 
carefully  weighed.  The  difference  in  weight  gives 
the  amount  of  zinc  taken.  This  is  freely  acidified 
with  hydrochloric  acid,  and  heated  to  the  boiling 
point,  two  or  three  drops  of  uranic  solution  added, 
and  the  ferrocyanide  delivered  into  the  solution  from 
a  stoppered  burette.  White  ferrocyanide  of  zinc  is 
precipitated,  and,  as  the  drops  of  ferrocyanide  fall 
into  the  solution,  a  brown  spot  of  ferrocyanide  of 
uranium  appears,  but  disappears  again  on  stirring 
so  long  as  free  zinc  exists  in  solution.  The  moment 
all  the  zinc  is  converted  into  ferrocyanide  the 
addition  of  the  test  solution  tints  the  whole  liquid 
brown.  Before  this  point  is  reached,  and  as  the 
brown  spot  disappears  more  slowly,  a  porcelain  plate 
should  be  placed  by  the  side  of  the  operator.  A 
number  of  spots  of  uranium  nitrate  solution  are 
dropped  on  the  plate  from  a  glass  rod.  A  drop  of 
the  mixture  is  taken  from  the  beaker  by  means  of  a 
glass  rod,  and  brought  into  contact  with  one  of  the 
uranic  spots.    If  no  brown  colour  be  produced  the 


Analysis  of  Chloride  of  Zinc.  251 

ferrocyanide  is  added  drop  by  drop  until  the  mixture 
in  the  beaker  produces  a  brown  tint  on  coming  in 
contact  with  one  of  the  spots  of  uranium  nitrate 
solution.  It  is  necessary  to  make  a  blank  test  with 
the  standard  zinc  solution  and  standard  ferrocyanide 
of  potassium  solution  before  commencing  the 
analysis  of  a  sample  of  chloride  of  zinc,  and  when 
the  shade  of  colour  produced  in  the  actual  analysis 
of  the  chloride  of  zinc  is  the  same  as  in  the  titration 
of  the  standard  zinc  solution,  the  process  is  ended. 

The  number  of  c.c.  of  ferrocyanide  solution  used 
is  multiplied  by  o*oi.  This  gives  the  amount  of 
metallic  zinc  in  the  solution,  which  should  be 
calculated  to  chloride.  Each  65  parts  by  weight  of 
zinc  is  equivalent  to  136  parts  by  weight  of  chloride 
of  zinc.  The  amount  of  chloride  of  zinc  found  in 
the  weight  of  solution  taken  is  calculated  to  a 
percentage. 

The  gravimetric  process  is  carried  out  as 
follows  : — A  weighed  quantity  of  the  solution  of 
chloride  of  zinc  is  diluted  with  water  and  acidified 
with  hydrochloric  acid  in  a  beaker,  then  boiled. 
Nitric  acid  is  added  to  convert  ferrous  iron  (if 
present)  into  ferric.  Excess  of  ammonia  and  chloride 
of  ammonium  are  added  to  precipitate  the  ferric 
hydrate,  and  sufficient  to  dissolve  the  hydrate  of 
zinc.  The  mixture  is  filtered,  and  washed  with 
ammonia  and  water,  and  the  washings  added  to  the 
solution  of  zinc.     The  precipitate  is  re-dissolved  in 


252       The  Chemistry  and  Practice  of  Sizing, 

hydrochloric  acid,  and  re-precipitated  as  directed 
in  the  volumetric  estimation.  The  mixed  filtrates 
are  treated  with  an  excess  of  solution  of  sulphide  of 
ammonium.  The  liquid  is  set  aside  for  some  hours 
and  then  filtered  through  a  filter  paper,  the  amount 
of  ash  of  which  is  known.  The  precipitate  is 
thoroughly  washed  with  dilute  solution  of  sulphide 
of  ammonium,  dried,  and  transferred  to  a  weighed 
crucible  and  ignited  for  some  time  at  a  bright  red 
heat.  The  filter  paper  is  rolled  up  and  wrapped 
round  with  a  piece  of  platinum  wire  so  as  to  form  a 
cage,  and  burnt  to  a  white  ash  in  the  Bunsen's  flame. 
The  ash  is  added  to  the  crucible  and  the  whole 
ignited.  The  crucible  and  contents  are  cooled  and 
weighed,  and  from  the  oxide  of  zinc  found,  the  weight 
of  the  filter  paper  ash  is  deducted.  The  oxide  is 
calculated  to  chloride,  and  the  chloride  to  a  percentage 
of  the  weight  of  chloride  of  zinc  originally  taken. 

N.B. — Care  must  be  taken  that  the  sulphide 
of  zinc  is  removed  (after  drying)  from  the 
filter  paper  without  detaching  any  of  the  paper, 
otherwise,  as  the  paper  carbonises  when  heated  in 
the  crucible,  a  portion  of  the  oxide  of  zinc  formed 
will  be  converted  into  metallic  zinc,  and  so  lost  by 
volatilization.  It  is  better  to  ignite  in  the  presence 
of  nitrate  of  ammonium. 

The  following  table,  marked  No.  1,  shows  the 
composition  of  commercial  chlorides  of  zinc  of  good 
average    quality  which    have    been    analysed  at 


Analysis  of  Chloride  of  Zinc.  253 

various  times  by  the  writer.  The  table  marked 
No.  2  shows  the  composition  of  some  adulterated 
samples,  except  in  the  case  of  No.  4.  This  latter 
sample  was  badly  prepared,  and  it  contained  an 
excessive  and  dangerous  quantity  of  chloride  of  iron. 


Table  No.  1. 


No.  1. 
per  cent. 

No.  2. 

per  cent. 

No.  3. 
per  cent. 

No.  4. 

per  cent. 

Chloride  of  zinc   

Chloride  of  Magnesium  ... 

41  644 
1-378 
trace 

43*77 
1-87 

45*44 
•37 
76 

45*74 
trace 
074 

Chloride  of  sodium   

Water  

1-470 
55'5°8 

1*24 
53*i2 

1  04 

52'39 

°*97 
52-55 

IOO'OOO 

100  00 

IOO'OO 

IOO'CO 

Specific  gravity  

Equal  to  degrees  Twaddell 

1*46 
92°T 

i*49 
98T 

io4°T 

1518 

io3-6°T 

The  above  table  should  be  compared  with  the 
one  below.     The  solutions  in  Table  No.  2  have 


been  submitted  to  the  writer  at  various  times,  as 


pure  samples  of  chloride  of  zinc,  but  on  analysis 
they  have  been  found  to  be  adulterated. 

Table  No.  2. 


Chloride  of  calcium  

Chloride  of  magnesium... 
Chloride  of  iron  

No.  1. 
per  cent. 

No.  2. 
per  cent. 

No.  3. 
per  cent. 

No.  4. 
per  cent. 

3I*3I 

078 

trace 

18-43 
1  [78 

trace 
trace 
12*17 
57-62 

33*74 
0-79 
13*12 

40*04 
112 

6*oi 
0*67 
52*16 

Chloride  of  sodium  .... 
Water  

n'37 

56'54 

0*78 
5T*57 

IOO'OO 

IOO'OO 

I0O"O0 

IOO'OO 

254       The  Chemistry  and  Practice  of  Sizing. 


Apparently  the  amount  of  adulteration  in  the 
first  case  is  1 1  per  cent.,  but  it  is  really  very  much 
more.  Pure  chloride  of  zinc  solution  contains  about 
45  per  cent,  of  the  solid  chloride,  so  that  the  actual 
adulteration  is  about  26  per  cent. 

Use  of  Chloride  of  Zinc  in  Sizing. 

A  great  difference  of  opinion  exists  amongst 
manufacturers  as  to  the  best  method  of  using 
chloride  of  zinc  or  other  antiseptics.  It  should 
be  remembered  that  the  best  results  are  always 
obtained  by  bringing  into  the  closest  contact  those 
substances  likely  to  mildew,  or  decompose,  with  those 
substances  which  are  being  used  to  preserve  them. 
It  is  not  necessary  to  preserve  mineral  matter  such 
as  China  clay  from  mildew,  so  it  is  no  advantage 
to  boil  the  zinc  with  the  clay,  as  is  very  often  done. 
The  proper  method  of  procedure  is  to  add  the 
chloride  of  zinc,  or  other  antiseptic,  to  the  flour, 
the  substance  which  will  mildew,  and  let  them  stay 
in  contact  as  long  as  convenient.  The  other 
ingredients  of  the  size  merely  dilute  the  chloride  of 
zinc,  and  thus  dilute  its  antiseptic  powers.  This 
matter  is  further  discussed  in  the  following  chapter 
on  size  mixing. 

By  careful  experiments  it  has  been  found  that 
8  per  cent,  of  real  chloride  of  zinc  (solid)  to  the  starch 
or  flour  used,  or  3^  to  4  gallons  of  good  chloride  of 
zinc  to  each  sack  of  flour  (280  lbs.)  is  sufficient  to 


Use  of  Chloride  of  Zinc  in  Sizing.  255 


preserve  it  from  mildew  under  any  ordinary  con- 
ditions. It  must  be  remembered  that  this  proportion 
is  sufficient  where  the  warps  are  run  reasonably  dry, 
and  where  the  cloth  is  afterwards  kept  from  getting 
excessively  damp,  but  it  is  not  sufficient  if  the  cloth 
be  treated  to  extraordinary  usage.  Such  a  percent- 
age of  chloride  of  zinc  is  not  certain  to  preserve  a 
cloth  from  mildew  if  it  be  allowed  to  get  wet  and  is 
afterwards  packed  damp,  and  the  authors  have  con- 
siderable doubts  as  to  the  preserving  power  of  any 
excessive  quantity  of  chloride  of  zinc  in  such 
circumstances. 

Other  substances  are  used  occasionally  as 
antiseptics  for  size,  but  unless  there  is  a  special 
stipulation  against  the  use  of  chloride  of  zinc,  as 
instanced  by  goods  intended  to  be  bleached,  it  is  by 
far  the  most  suitable  antiseptic  for  sizing  purposes 
generally.  The  cost  is  low  and  the  results  definite. 
Moreover  in  medium  and  heavy  sizing  it  has  one 
special  advantage;  it  assists  in  getting  the  necessary 
weight.  This  is  a  matter  of  considerable  importance 
in  heavy  sizing. 

It  may  be  advisable  to  warn  manufacturers  once 
more  at  this  stage  against  the  use  of  secret  pre- 
parations. Many  cases  of  damage  to  fabrics  which 
have  been  singed  are  traceable  to  the  use  of  secret 
preparations  which  have  contained  chloride  of  zinc 
and  chloride  of  magnesium,  The  manufacturer  is 
unaware  that  he  is  using  such  chemicals  in  his  size, 


256      The  Chemistry  and  Practice  of  Sizing. 


and  his  surprise  is  generally  very  great  indeed  when 
he  has  the  responsibility  for  the  damage  placed 
upon  him. 

SALICYLIC  ACID— CGH4OH-COOH. 

Salicylic  acid  occurs  in  the  form  of  white 
crystals,  and  it  is  one  of  the  most  powerful 
antiseptics  known.  It  is  prepared  by  acting  upon 
pure  carbolic  acid  (phenol)  with  carbon  dioxide. 
The  carbolic  acid  is  first  saturated  with  caustic  soda. 
This  converts  the  carbolic  acid  into  sodium-phenol 
or  carbolate  of  sodium,  CGH5'ONa.  The  carbolate 
of  sodium  is  then  saturated  with  carbon  dioxide  at 
the  ordinary  temperature,  by  which  phenylcarbonate 
of  sodium  is  produced.  The  latter  substance  is  con- 
verted into  salicylate  of  sodium  on  gradually  heating 
in  closed  vessels  to  a  temperature  of  450°  Fah. 
The  salicylate  of  sodium  is  converted  into  salicylic 
acid  by  the  action  of  hydrochloric  acid,  and  further 
purified  by  recrystallisation  from  alcohol.  The 
following  equations  will  illustrate  the  chemical 
changes  which  occur  in  the  process  of  manufacture: — 

C6H5-OH  +  NaHO  =  C6H5ONa  +  H20 
Carbolic  Acid.       Caustic  Soda.       Carbolate  of  Sodium.  Water. 

C(iH5-ONa      +      C02      =  CGH5OCO'ONa 

Carbolate  of  Sodium.      Carbon  Dioxide.      Phenylcarbonate  of  Sodium, 

C6H50'CO-ONa  on  heating       =  C6H4OH-COONa 

Phenylcarbonate  of  Sodium.  Salicylate  of  Sodium. 

C(;H4OHCO'ONa  +  HQ   =   C6H4OH'CO'OH  +  NaCl 
Salicylate  of  Sodium.       Hydro-  Salicylic  Acid.  Chloride  of 

chloric  Acid.  Sodium. 


Salicylic  Acid. 


257 


Use  of  Salicylic  Acid  in  Sizing. 

Salicylic  acid  is  a  useful  antiseptic,  but  until 
recent  years  it  has  been  too  costly  to  be  used  in 
sizing.  The  price  is  much  lower  at  the  present 
time,  and,  as  an  antiseptic  for  "pure"  sized  yarns,  in 
which  chloride  of  magnesium  or  chloride  of  calcium 
are  not  ingredients  of  the  size,  it  cannot  be  surpassed. 
Although  an  acid  it  has  no  objectionable  features, 
and  it  is  as  effective  as  chloride  of  zinc  in  its 
antiseptic  properties  lor  "pure"  sizing.  Considering 
the  amount  of  this  substance  which  is  required  to 
prevent  mildew  growths,  it  is  as  cheap  as  chloride  of 
zinc.  Six  ounces  of  salicylic  acid,  to  each  100 
pounds  of  starch,  are  sufficient  to  prevent  mildew 
under  ordinary  conditions.  When  wheaten  flour  is 
used  it  will  be  advisable  to  use  eight  ounces,  as  flour 
has  a  greater  tendency  to  generate  mildew  than  the 
pure  starches. 

Salicylic  acid  is  only  slightly  soluble  in  cold 
water,  but  it  is  readily  soluble  in  boiling  water.  On 
this  account  it  is  necessary  to  first  dissolve  the  acid 
in  boiling  water,  and  add  the  solution  formed  to 
the  size  mixing. 

When  salicylic  acid  is  used  as  an  antiseptic  in 
"pure"  sized  yarns  for  goods  which  are  intended  to 
be  sold  in  the  grey  state,  it  is  possible  to  employ 
glycerine  in  the  size.  As  previously  stated,  glycerine 
has  a  powerful  tendency  to  absorb  moisture,  and 

on  this   account    the   yarn  is  very  considerably 

Q 


258      The  Chemistry  and  Practice  of  Sizing. 

strengthened,  and  the  weaving  considerably  im- 
proved. It  would  not  be  advisable  to  employ 
glycerin  without  salicylic  acid  for  such  goods,  as  it 
might  be  the  means  of  developing  mildew. 

It  may  be  as  well  to  state  here  that  salicylic  acid 
loses  its  antiseptic  properties  if  free  caustic  alkali, 
such  as  caustic  soda,  or  caustic  potash,  be  an 
ingredient  of  the  size. 

THYMOL. 

This  powerful  antiseptic  is  a  camphor  obtained 
from  thyme  oil,  and  horsemint  oil.  It  is  extracted 
by  agitating  the  oil  with  a  solution  of  caustic  soda. 
The  aqueous  layer  is  separated  and  treated  with 
an  excess  of  dilute  hydrochloric  acid  when  thymol 
separates  out  as  an  oily  layer.  It  may  be  obtained 
from  the  oil  by  submitting  it  to  a  low  temperature 
when  the  thymol  crystallises  out. 

Thymol  is  very  slightly  soluble  in  water,  1  pound 
requiring  about  1,200  pounds  of  water  to  completely 
dissolve  it.  A  delicate  test  for  thymol  consists  in 
heating  the  solution  with  half  its  measure  of  glacial 
acetic  acid,  and  its  own  measure  of  concentrated 
sulphuric  acid,  A  fine  violet-red  colouration  is 
produced  which  is  not  destroyed  by  boiling. 

The  only  draw-back  to  the  use  of  thymol  in 
"pure"  sizing  is  its  price,  otherwise  it  leaves  nothing 
to  be  desired. 


Carbolic  Acid. 


259 


CARBOLIC  ACID— Phenol  (C6H5OH). 

This  substance  is  a  powerful  antiseptic  which  is 
occasionally  used  in  sizing.  The  only  objectionable 
feature  it  possesses  is  its  powerful  odour.  Carbolic 
acid  is  obtained  from  coal  tar  by  fractional  distilla- 
tion. It  is  contained  in  that  portion  which  distils 
over  between  300°  and  390°  Fah.  The  product 
of  distillation  is  treated  with  caustic  soda.  This 
alkali  dissolves  the  carbolic  acid,  together  w7ith 
a  certain  amount  of  napthalene.  The  alkaline 
solution  is  purified  by  a  treatment  with  sulphuric 
acid  which  liberates  the  carbolic  acid.  This  is 
further  purified  by  again  treating  with  caustic  soda 
and  afterwards  with  sulphuric  acid.  The  oily  liquid 
thus  obtained  is  then  distilled,  that  portion  passing 
over  into  the  receiver  at  a  temperature  of  360°  Fah., 
being  subjected  to  a  freezing  mixture.  By  this 
treatment  the  carbolic  acid  crystallises  out,  and  is 
separated  from  the  mother  liquor  by  means  of  a 
centrifugal  machine.  The  product  may  be  further 
purified  by  a  repetition  of  the  processes. 

Pure  carbolic  acid  is  a  colourless  solid,  soluble 
in  water  to  the  extent  of  1  part  in  1,200.  5  to  10 
per  cent,  of  water  liquefies  the  acid,  which  will  then 
dissolve  about  30  per  cent,  more  water.  The  acid 
is  soluble  in  alcohol,  ether,  glacial  acetic  acid,  and 
glycerin. 

Commercial  carbolic  acid  almost  invariably  turns 
red  when  exposed  to  light.     For  sizing  purposes 


260      The  Chemistry  and  Practice  of  Sizing. 

pure  carbolic  acid  is  not  used,  the  variety  known  as 
No.  5  carbolic  acid  being  generally  employed.  It  is 
as  actively  antiseptic  as  the  pure  acid.  The  No.  5 
carbolic  acid  consists  largely  of  cresylic  acid. 
Crude  carbolic  acid  has  a  specific  gravity  of  105  to 
1*065  at  a  temperature  of  6o°  Fah.  Carbolic 
acid  is  frequently  adulterated,  the  principal  sub- 
stances used  being  water  and  tar  oils.  Neither 
of  these  substances  has  antiseptic  value.  The 
antiseptic  value  of  different  samples  of  carbolic 
acid  may  be  ascertained  by  making  samples  of 
flour  paste,  using  in  each  case  the  same  quantity  of 
flour  and  water.  To  each  paste  is  added  a  certain 
proportion  of  the  carbolic  acid  under  examination 
and  after  this  has  been  well  stirred  into  the  mass, 
the  mixture  is  poured  on  plates,  so  that  a  surface, 
as  large  as  possible,  may  be  exposed  to  the  air. 
The  samples  are  allowed  to  stand,  and  should  be 
examined  each  day.  The  one  first  showing  signs 
of  mildew  is  the  weakest  in  antiseptic  value.  A 
suitable  flour  paste  may  be  made  by  mixing  10 
grammes  of  flour  with  100  c.c.  of  water  and  heating 
as  described  on  page  55. 

CRESYLIC  ACID.— Cresol. 

Cresylic  acid  is  obtained  from  coal  tar.  It  is  that 
portion  left  in  the  retort  after  the  carbolic  acid  has 
distilled  over.  Cresylic  acid  closely  resembles  car- 
bolic acid  in  its  properties,  but  it  is  a  liquid  whereas 


Cresylic  Acid. 


261 


carbolic  acid  is  a  solid.  It  is  less  soluble  in  water 
and  boils  at  a  higher  temperature  than  carbolic  acid. 
Like  carbolic  acid,  the  only  objection  to  its  use  as 
an  antiseptic  for  sizing  purposes  is  the  strong  odour, 
similar  to  that  of  carbolic  acid,  which  it  possesses. 
It  is  a  more  powerful  antiseptic  than  chloride  of 
zinc. 

Neither  carbolic  nor  cresylic  acids  have  the  usual 
properties  of  ordinary  acids,  and  they  are  in  no 
way  objectionable  substances  to  use  where  coloured 
goods  are  being  treated. 

For  the  purpose  of  preventing  mildew  in  sized 
goods,  10  ounces  of  either  carbolic  or  cresylic  acid 
should  be  used  to  each  100  pounds  of  starch. 


262        The  Chemistry  and  Practice  of  Sizing. 


Chapter  VII. 

Size  Mixings, 
and  the  Methods  and  Plant  employed 
in  Mixing  Size. 


CLASSIFICATION  OF  SIZING. 

BEFORE  describing  the  plant  used  in  mixing 
size,  and  before  dealing  with  the  operations 
involved  in  sizing,  it  will  be  necessary  to  discuss  the 
principal  objects  for  which  sizing  is  carried  out. 

Originally  sizing  was  carried  out  with  the  sole 
object  of  giving  the  yarn  sufficient  strength  to  enable 
it  to  be  successfully  woven  into  cloth.  At  the  present 
time  sizing  is  carried  out  with  a  great  number  of 
objects,  not  the  least  important  of  which  is  the 
production  of  a  certain  desired  "feel"  in  the  cloth. 

For  the  sake  of  convenience  in  description 
sizing  may  be  classified  under  four  heads,  viz. : — 
"Pure"  Sizing;  "Light"  Sizing;  "Medium"  Sizing; 
and  "Heavy"  Sizing. 


"Pure"  Sizing. 


263 


"Pure"  Sizing. — In  "pure"  sizing  the  main 
object  is  to  give  the  yarn  sufficient  strength  to 
withstand  the  friction  of  the  healdsand  reeds  during 
the  process  of  weaving,  without  increasing  the 
weight  of  the  cloth  unnecessarily. 

A  large  proportion  of  "pure"  sized  goods  are 
intended  for  bleaching.  In  many  cases  the  goods 
have  to  be  dyed  or  printed  after  this  operation.  The 
operations  involved  in  bleaching  remove  the  whole 
of  the  size  from  the  cloth.  On  this  account  it  is 
advisable  to  put  as  small  a  quantity  of  size  on  the 
yarn  as  is  consistent  with  good  weaving.  Any  excess 
of  size  is  not  only  an  increase  in  the  cost  of  sizing, 
but  it  renders  the  cloth  more  expensive  to  bleach, 
on  account  of  the  extra  boiling  and  washing 
required.  Under  no  circumstance  should  chloride 
of  magnesium,  paraffin  wax,  or  tallow  adulterated 
with  mineral  oil  or  other  unsaponifiable  substance 
be  used  as  an  ingredient  of  size  if  the  goods  are 
intended  to  be  bleached. 

Size  for  a  "pure"  mixing  is  usually  composed  of 
starchy  substances  of  some  description,  with  fatty 
matter,  and  water.  Such  mixtures  are  usually 
prepared  from  either  flour,  farina,  sago,  or  a  com- 
bination of  such  starches  as  farina  and  sago,  together 
with  a  sufficient  amount  of  some  "softener,"  such  as 
tallow,  soap,  or  wax.  The  effect  of  the  "softener" 
is  to  render  the  yarn  pliable  and  so  assist  the 
weaving.     Chloride  of  zinc  is  sometimes  added  to 


264      The  Chemistry  and  Practice  of  Sizing, 

"pure"  size  in  order  to  prevent  the  formation  of 
mildew  in  cloth  which  is  intended  for  shipment  in 
the  grey  state.  Salicylic  acid  is  also  being  used  for 
this  purpose,  as  stated  on  page  257. 

It  may  be  taken  as  a  rule  that  "pure"  size  should 
be  free  from  China  clay  and  chloride  of  magnesium. 
Occasionally  China  clay  is  employed  in  "pure" 
size  to  increase  the  pliability  of  the  yarn.  This  is 
not  necessary,  as  a  similar  result  could  be  obtained 
without  China  clay  if  an  increased  quantity  of  tallow 
were  used  in  the  mixing.  The  proportion  of 
tallow  or  wax  should  also  be  small  in  comparison 
with  the  proportion  of  starchy  matter,  because, 
although  a  right  proportion  of  these  softeners 
make  the  yarn  pliable,  an  excessive  amount  has 
a  tendency  to  make  the  size  friable.  This  has 
the  effect  of  causing  the  size  to  rub  off  in  the 
healds  and  reeds. 

The  substances  used  for  "pure"  sizing  vary 
considerably  in  different  districts  for  the  same  class 
of  cloth.  In  certain  districts  there  seems  to  be  a 
desire  to  use  as  many  ingredients  as  possible.  It  is 
not  unusual  to  find  a  "mixing"  containing  farina, 
sago,  Irish  moss,  tallow,  paraffin  wax,  spermaceti, 
castile  soap,  white  soap,  gum  tragacanth,  and 
bi-carbonate  of  soda.  Why  all  these  ingredients 
are  used,  or  what  there  is  to  be  gained  by  such 
a  conglomeration  of  substances,  is  a  mystery  which 
would  probably  puzzle  the  users  to  explain. 


"Light"  Sizing. 


265 


Quite  as  good  results  are  obtained  in  other 
districts  with  less  trouble  and  greater  economy  by 
using  a  mixture  of  say,  sago  and  farina,  with  either 
tallow  or  paraffin  wax. 

At  some  future  date,  when  sizing  is  better 
understood,  these  complicated  mixtures,  and  the 
various  nostrums  at  present  used  in  "pure"  sizing, 
will  be  replaced  by  simpler  and  more  economical 
l<  mixings."  The  only  losers  by  the  change  will  be 
the  vendors. 

"Light"  Sizing. — ''Light"  sizing  is  generally 
understood  to  mean  that  in  which  the  twist  is 
weighted  to  the  extent  of  from  about  20  to  30 
per  cent.  Such  a  weight  can  be  obtained  by  the 
use  of  a  "mixing"  consisting  of  flour,  tallow,  and 
water  only,  see  page  73.  As  a  general  rule, 
however,  a  "mixing"  for  "light"  sizing  will  contain 
all  the  ingredients  used  for  "medium"  and  "heavy" 
size,  but  in  different  proportions.  It  will  be  found 
that  as  44  mixings "  increase  in  strength,  the  per- 
centage of  China  clay,  chloride  of  magnesium,  and 
tallow  increases,  whilst  the  percentage  of  starchy 
matter  decreases. 

"Medium"  Sizing. — In  "medium"  sizing  the 
object  is  not  only  to  put  sufficient  size  on  the  yarn 
to  enable  it  to  resist  the  rubbing  of  the  healds  and 
reeds,  but  it  is  carried  out  with  the  object  of  adding 
weight  to  the  cloth,  together  with  the  production  of 
a  certain  "  feel."    This  "  feel  "  is  quite  as  important 


266      The  Chemistry  and  Practice  of  Sizing, 

as  the  weight  in  many  cases.  The  constituents 
of  the  size  for  u  medium"  sizing  are  usually  water, 
starchy  matter,  China  clay,  chloride  of  magnesium, 
tallow,  and  chloride  of  zinc. 

"Heavy"  Sizing. — This  form  of  sizing  is  carried 
out  with  the  object  of  introducing  a  very  large 
amount  of  size  into  the  cloth.  This  is  done  in  order 
to  give  the  cloth  a  better  and  fuller  appearance 
than  it  would  be  possible  to  give  with  the  same 
monetary  value  in  cotton  alone.  Size  for  this  class 
of  work  is  composed  of  ingredients  similar  to  those 
used  in  "medium"  sizing,  but  the  proportions  are 
altogether  different. 

In  "heavy"  and  more  particularly  in  very 
"heavy"  sizing,  the  yarn  must  be  taken  into 
consideration  as  well  as  the  sizing  ingredients. 
At  the  present  time  ring  spun  yarn  is  largely 
superseding  mule  spun  yarn  for  "pure"  and  "light" 
sizing,  but  it  is  much  more  difficult  to  heavily 
size  ring  yarn  to  the  same  extent  as  mule  yarn. 
This  is  owing  to  the  fact  that  ring  yarn  is  harder 
spun  than  mule  yarn.  The  extra  number  of  turns 
of  twist  per  inch  in  this  yarn  reduce  the  interstices 
between  the  fibres  of  which  the  thread  is  composed. 
There  is,  therefore,  less  space  to  be  filled  up  with 
size.  On  account  of  this  difference  in  spinning  the 
diameter  of  a  thread,  for  the  same  counts,  will  also 
be  less  with  ring  yarn  than  it  is  with  mule  yarn. 
This  means  that  there  is  less  outside  surface  in  ring 


Arrangement  of  Size  Mixing  Plant.  267 

spun  yarns  to  put  the  "size"  on.  The  difference 
in  the  interstices  between  the  fibres,  and  the 
difference  in  the  diameters  of  ring  spun  yarn  and 
mule  spun  yarn,  may  be  small,  but  they  also  make 
a  great  deal  of  difference  in  the  results  in  " heavy" 
sizing.  It  must  be  remembered  that  the  ingredients 
used  in  size  are  mostly  insoluble  substances,  and,  as 
such,  they  cannot  enter  into  the  fibres  forming  the 
thread,  but  are  simply  pressed  on  the  surface,  and  into 
the  spaces  between  the  fibres.  This  being  so,  it  must 
follow  that  those  yarns  which  are  known  as  "soft 
spun"  yarns,  on  account  of  their  having  a  less 
number  of  turns  per  inch,  and  which  are  therefore 
not  so  tightly  spun,  are  the  best  for  "heavy" 
sizing. 

ARRANGEMENT  OF  PLANT  IN  SIZE 
MIXING  ROOMS. 

The  arrangement  of  the  size  mixing  apparatus 
and  the  number  of  becks  and  pans  required  for  a 
given  number  of  looms  depends,  to  a  great  extent, 
upon  the  class  of  cloth  it  is  intended  to  produce. 
In  a  mill  where  only  "pure"  sizing  is  carried  out 
the  plant  required  is  small  as  compared  with  a  mill 
in  which  a  large  variety  of  sized  goods  are  manu- 
factured. For  "pure"  sizing,  unless  flour  is  one  of 
the  ingredients  of  the  size,  one  or  two  small  becks 
will  be  ample.  If  flour  be  used  it  will  be  necessary 
to  have  at  least  two  additional  becks,  one  to  be  used 


268       The  Chemistry  and  Practice  of  Sizing 


for  fermenting  or  for  steeping  the  flour,  whilst  the 
other  should  be  used  to  store  the  prepared  flour. 

For  " medium"  and  " heavy"  sizing  a  clay  pan 
and  a  beck  for  the  chloride  of  magnesium  will  be 
required.  If  it  be  intended  to  use  a  variety  of 
"  mixings  it  will  be  necessary  to  have  a  number  of 
extra  becks  in  which  the  various  strengths  of  size 
may  be  stored. 

A  detailed  description  of  the  construction  of  the 
size  becks  is  unnecessary  in  a  book  of  this  kind,  and 
the  practical  man  should  be  fully  conversant  with 
them.  At  the  same  time  a  few  words  in  regard  to 
the  arrangement  of  the  apparatus  may  serve  a  useful 
purpose.  Unfortunately  in  many  of  the  older  types 
of  mills  the  plant  has  been  arranged  more  with  a 
view  to  utilising  the  space  at  the  manufacturers 
disposal  than  with  the  object  of  enabling  the  size- 
mixer  to  perform  his  work  with  as  little  labour  as 
possible.  Haphazard  arrangement  of  this  kind 
generally  necessitates  manual  labour  for  the  purpose 
of  lifting  and  carrying  the  whole  of  the  sizing 
ingredients  to  the  different  becks  and  pans.  Under 
such  conditions  the  floors  of  the  rooms  and  the  sides 
of  the  "  mixing"  becks  become  covered  with  an  accu- 
mulation of  the  ingredients  used  in  the  size.  Such 
conditions  are  not  conducive  to  either  cleanliness  or 
to  economy.  The  plant  in  all  modern  size-mixing 
rooms,  whether  the  rooms  are  built  on  the  ground 
floor  or  contained  in  a  two-storied  building,  should 


Arrangement  of  Size  Mixing  Plant.  269 

be  so  arranged  that  the  size-mixer  has  practically  no 
lifting  or  carrying  to  do  when  putting  down  flour  to 
steep,  or  mixing  China  clay,  or  making  a  "mixing." 

In  a  well-equipped  mill,  where  it  is  intended  to 
manufacture  u  medium  "  or  "  heavy  "  sized  shirtings, 
the  size-rooms  and  machinery  should  be  arranged 
as  follows  : — 

The  size-rooms  should  be  contained  in  a  two- 
storied  building ;  the  upper  room  being  used  as 
the  store-room.  This  room  should  contain  a  hoist, 
which  is  used  for  the  purpose  of  raising  all  the 
ingredients  (except  the  chloride  of  magnesium),  to 
the  upper  floor. 

The  flour  becks,  clay  pan,  mixing  becks,  and 
the  beck  for  the  chloride  of  magnesium,  should  be 
arranged  on  the  ground  floor.  A  number  of 
"shoots"  should  be  arranged  leading  from  the 
floor  of  the  store-room  to  the  flour  becks  and  clay 
pan.  These  shoots  are  used  to  convey  the 
ingredients  from  the  upper  storey  to  the  beck 
or  pan  in  which  it  is  intended  to  mix  them. 

If  the  size-mixing  rooms  are  arranged  in  the 
above  manner,  very  little  manual  labour  will  be 
entailed  in  emptying  the  various  ingredients.  A 
model  arrangement  of  a  size- mixing  room  is  shown 
on  plate  xi. 

The  pipes,  leading  from  the  becks  to  the  pump, 
ought  to  be  at  least  two  inches  in  diameter,  in  order 
to  avoid  trouble  when  pumping  the  size.   The  pump 


2  jo       The  Chemistry  and  Practice  of  Sizing. 


should  not  be  less  than  three  inches  in  diameter,  and 
it  should  have  a  long  lift,  with  a  fewer  number  of 
strokes,  in  preference  to  a  short  lift,  with  a  higher 
speed.  The  pump  ought  to  be  coupled  up  to  every 
beck  and  pan  in  the  size  room  (the  chloride  of 
magnesium  beck  excepted)  on  both  the  intake  and 
delivery  sides,  so  that  size  can  be  pumped  from  any 
one  beck  to  any  other.  All  changes  of  direction  in 
the  piping  should  be  made  with  bends  of  a  long 
sweep,  in  order  to  avoid  placing  unnecessary  work 
on  the  pump,  which  is  the  case  when  short  elbows 
and  sharp  bends  are  employed. 

Where  the  size  has  to  be  pumped  long  distances 
it  is  advisable  to  have  the  pump  driven  by  a 
separate  strap  instead  of  by  the  one  which  drives 
the  mixing  beck. 

When  it  is  intended  to  go  in  for  a  variety  of 
sizing  it  is  advisable  to  have  the  mechanism  of 
the  becks  and  pans  sufficiently  strong  to  deal 
wTith  the  heaviest  kind  of  size,  as  the  power 
required  to  turn  the  contents  of  becks  filled  with 
" heavy"  size  is  very  considerable. 

Flour  Becks. — These  becks  should  be  arranged 
on  a  higher  level  than  those  used  for  mixing  the 
size,  so  that  the  flour  in  steep  may  be  run  from  one 
beck  to  the  other  by  force  of  gravity. 

Mixing  Becks. — The  number  of  mixing  becks 
required  in  the  size-room  depends,  as  previously 
stated,  upon  the  variety  of  sized  goods  manufactured. 


A  rrangement  of  Size  Mixing  Plant.  271 

Where  "pure"  sized  goods  only  are  made,  and  where 
flour  is  not  used,  one  beck  only  may  suffice.  This 
beck  should  be  divided  into  two  or  more  compart- 
ments. It  will  then  serve  both  for  the  mixing  beck 
and  for  the  tapers  beck.  The  compartments  of 
the  beck  are  often  fitted  with  one  agitator  only. 
This  is  not  as  suitable  an  arrangement  for  producing 
uniform  "  mixings"  as  a  beck  fitted  with  two  or 
more  agitators  in  each  compartment.  If  more  than 
one  agitator  be  fitted  in  a  compartment  they  should 
be  arranged  so  as  to  just  clear  when  at  right  angles 
to  each  other.  Size  can  be  mixed  more  uniformly, 
and  the  ingredients  worked  into  finer  particles  in 
far  less  time  when  two  agitators  are  fitted  as  shown 
in  plate  xi,  than  when  the  two  agitators  have  room 
to  clear  when  they  are  in  a  straight  line. 

Chloride  of  Magnesium  Beck. — This  beck 
should  be  arranged  so  that  the  top  of  the  beck  is 
either  on  or  below  the  floor  level  in  the  lower  room. 
Arranged  in  this  manner  a  great  deal  of  time  and 
work  is  saved,  and  the  chloride  of  magnesium  is 
more  easily  handled  when  this  substance  is  being 
dissolved  out  by  steam.  The  beck  should  be  lined 
with  sheet  lead,  in  order  to  prevent  the  chloride  of 
magnesium  percolating  through  to  the  wood. 

The  chloride  of  magnesium  beck  should  be 
provided  with  an  ejecter  leading  to  the  clay  pan. 

Clay  Pan. — The  clay  pan  should  be  provided 
with  an  iron  cover,  fitted  with  a  hinged  lid,  in  order 


272      The  Chemistry  and  Practice  of  Sizing. 

that  the  contents  of  the  pan  may  be  examined  when 
required.  When  the  clay  is  being  boiled  the  lid 
should  be  closed. 

A  good  sized  pipe,  or  preferably  an  upright 
trunk,  passing  through  the  roof  of  the  building, 
should  be  fixed  to  carry  the  steam  away.  If  this 
trunk  be  of  sufficient  size  to  carry  the  steam  away 
quickly,  it  enables  the  size-mixer  to  keep  a  fair 
amount  of  "boil"  on  without  any  fear  of  the  clay 
spirting,  or  of  the  contents  of  the  pan  boiling  over. 
The  steam  used  in  boiling  also  helps  to  break  up 
the  clay,  on  account  of  the  additional  agitation 
imparted  to  the  contents  of  the  pan. 

Clay  pans  are  constructed  in  such  a  way  that  the 
lower  arm  of  the  agitator  is  from  one  to  three  inches 
from  the  bottom  of  the  pan.  This  space  gets  filled 
up  more  or  less  with  clay,  according  to  the  kind  of 
"mixing"  being  made.  Where  a  variety  of  ''mixings" 
are  used,  and  the  pan  is  a  large  one,  it  is  advisable 
to  make  some  allowance  for  the  amount  of  clay 
likely  to  be  left  in  this  space.  To  illustrate  more 
clearly  what  is  meant  by  this  statement,  let  it  be 
supposed  that  the  clay  pan  is  absolutely  clean,  and 
it  is  intended  to  be  used  for  a  very  heavy  "mixing," 
containing  10  bags  of  clay.  After  the  clay  has  been 
boiled,  and  the  contents  of  the  pan  emptied  as  far  as 
possible,  it  will  be  found,  on  examination,  to  contain 
a  considerable  amount  of  clay,  especially  on  the 
bottom  of  the  pan.    As  a  matter  of  fact,  half  a  bag 


Mixing  China  Clay.  273 


to  a  bag  of  clay  might  be  easily  left  in  the  pan,  so 
that  if  no  allowance  be  made  for  this,  the  ''mixing" 
might  contain  9  to  9^  bags  of  clay  only,  instead  of 
the  10  intended. 

After  making  a  "mixing"  of  this  description,  let 
us  assume  that  the  pan  is  next  used  for  a  lighter 
"mixing"  containing  two  bags  of  clay.  As  this 
mixing  would  have  a  larger  proportion  of  water  to 
the  two  bags,  than  the  previous  one  had  to  the  ten, 
the  result  would  be  that  a  large  portion  of  the  clay 
which  had  been  left  in  the  pan  from  the  previous 
"mixing"  would  get  worked  loose  from  the  pan 
bottom,  and  become  incorporated  in  the  second 
"mixing."  This  might  then  contain  2^  to  2f  bags 
of  clay,  instead  of  the  two  intended.  This  irregularity 
in  the  proportion  of  clay  is  one  of  the  chief  sources 
of  irregular  "mixings,"  and  it  is  one  that  causes 
great  variations  in  the  strength  of  the  "mixings," 
and  in  the  proportion  of  ingredients  present.  It 
also  accounts  for  the  variations  in  the  "feel"  and 
the  appearance  of  cloth  which  is  supposed  to  be 
sized  with  similar  "mixings." 

PREPARATION  OF  THE  VARIOUS 
SIZING    INGREDIENTS    PREVIOUS  TO 
"MIXING." 

The  sizing  ingredients,  and  the  various  propor- 
tions used  in  a  4 'mixing,"  are  generally  kept  as  secret 
as  ordinary  care  will  allow,  and  there  are  not  a  few 

R 


274      The  Chemistry  and  Practice  of  Sizing. 

manufacturers  who  assert  that  the  "mixing"  used  by 
them  contains  some  mysterious  ingredient  which 
makes  their  "mixing"  superior  to  any  other.  The 
authors  do  not  intend  to  divulge  any  of  these 
wonderful  secrets  for  the  simple  reason  that  they 
believe  that  the  men  who  make  such  statements  do 
so  either  in  a  spirit  of  braggadocio,  or  because  they 
are  ignorant  of  the  properties  of  the  special  ingredient 
they  are  using.  There  is  no  doubt  that  there  are 
certain  firms  who  do  obtain  far  better  results  in 
sizing  than  others,  but  this  is  due  more  to  the  care 
exercised  in  the  selection  of  sizing  ingredients  of 
good  quality,  and  to  systematic  methods  of  mixing 
them  together  in  suitable  proportions,  than  to  any 
special  ingredient  they  put  in. 

The  substances  generally  used  in  sizing  have 
already  been  dealt  with  under  various  headings  in 
another  portion  of  the  book.  These  ingredients 
are  all  that  the  manufacturer  need  employ  for  any 
"  mixing,"  if  care  be  taken  to  obtain  them  of  good 
quality. 

In  addition  to  the  ingredients  mentioned  in  the 
text,  there  are  many  others  used  in  sizing.  Most  of 
them  are  patent  (?)  softeners,  glycerin  substitutes, 
tallow  substitutes,  patent  emulsifiers,  secret  chemical 
mixings,  etc.  It  is  always  claimed  that  they  will 
produce  a  better  size,  bring  about  a  reduction  of  the 
tallow  usually  required,  save  the  healds  and  reeds, 
increase  the  average,  prevent  the  clay  dusting  off, 


Secret  Compounds  used  in  Sizing.  275 


and  make  a  cloth  which  will  command  a  higher 
price  than  can  be  obtained  by  the  use  of  the 
ordinary  ingredients.  There  is  one  thing,  however, 
that  the  dealers  in  these  wonderful  preparations 
never  mention  :  and  that  is,  that  these  nostrums 
are  produced  more  with  the  object  of  making 
large  profits  than  with  the  object  of  materially 
benefiting  the  user.  The  majority  of  these 
preparations  are  made  from  similar  ingredients  to 
those  in  general  use  in  the  mill,  and  the  chief 
addition  to  them  is  water. 

The  authors  have  no  hesitation  in  saying  that 
better  results  can  be  obtained  at  a  far  less  cost  by 
using  the  simple  ingredients,  mixed  in  a  systematic 
manner,  than  can  be  obtained  by  using  any  of  the 
mysterious  concoctions  offered  to  sizers. 

If  those  who  use  these  compounds,  which 
only  the  law  of  libel  prevents  the  authors  from 
naming,  only  knew  the  component  parts  of  many  of 
the  mixtures  they  purchase  to  put  in  the  size,  and 
the  percentage  of  water  contained  in  them,  they 
would  open  their  eyes  very  considerably. 

The  subject  of  excessive  moisture  in  cotton  is 
exercising  the  minds  of  many  people  at  the  present 
time,  yet  the  amount  of  excess  moisture  in  cotton 
is  a  mere  "  nothing"  compared  with  the  amount 
of  excess  moisture  in  many  substances  sold  as 
ingredients  for  size.  As  a  matter  of  fact,  many  of 
the  patent  (?)  softeners  contain  from  40  to  97  per 


276       The  Chemistry  and  Practice  of  Sizing. 

cent,  of  water.  This  water  is  always,  without  a  single 
exception,  driven  off  when  the  yarns  are  dried  on 
the  cylinders  of  the  tape-frame.  The  lost  portion 
of  the  ingredient  is  never  again  recovered,  so  far  as 
the  cloth  is  concerned.  When  it  is  considered  that 
from  £\o  to  £20  per  ton  is  paid  for  this  water  it 
will  be  evident  that  this  is  not  an  economical  way 
of  buying  sizing  ingredients.  If,  instead  of  using 
such  preparations,  the  manufacturer  would  exercise 
a  little  judicious  care  in  getting  out  the  quantities 
of  the  various  ingredients  necessary  for  any  size 
"  mixing,"  he  would  get  far  better  results  than  by 
trusting  to  some  kind  of  patent  (?)  softener  for 
which  the  seller  could  not  find  a  market  were 
it  not  for  the  ignorance  of  the  buyer.  Not  only 
would  his  results  be  better,  but  they  would  be 
attained  in  a  much  more  economical  way.  The 
authors  have  no  hesitation  in  stating  that  many 
firms  could  save  from  ^300  to  ,£500  per  annum  in 
their  sizing  bills  if  they  would  only  place  their  sizing 
arrangements  on  a  scientific  (common-sense)  basis. 
As  a  matter  of  fact  the  writer  has  reorganised  the 
sizing  in  certain  mills  where  as  much  as  ^2,000  per 
annum  has  been  saved,  and  better  results  have  been 
obtained  in  the  weaving. 

Before  going  into  details  in  regard  to  size 
"mixings"  it  will  perhaps  be  advisable  to  discuss 
the  ingredients  separately,  and  give  the  method  of 
treating  each  before  it  is  mixed  with  the  others. 


Treatment  of  Flour  in  Sizing. 


277 


This  matter  has  already  been  briefly  dealt  with  in 
the  previous  chapters,  and  the  authors  will  now  go 
more  fully  into  details. 

Treatment  of  Flour. — It  has  already  been 
stated  that  there  are  two  methods  of  treating 
flour  for  sizing  purposes,  viz.  : — By  fermentation, 
and  by  "steeping"  with  chloride  of  zinc.  In  the 
process  of  "steeping"  there  is  far  less  trouble,  and 
for  ordinary  sizing  the  authors  are  firmly  convinced 
that  more  uniform  results  are  obtained  than  can  be 
obtained  by  the  process  of  fermentation. 

The  "steeping"  process  is  to  be  preferred  to  the 
fermentation  process  for  several  reasons.  In  the 
first  place  it  prevents,  in  the  most  effective  manner, 
the  development  of  mildew  growths.  In  the  second 
place,  there  is  no  possibility  of  loss  on  account  of 
the  contents  of  the  beck  overflowing,  as  sometimes 
occurs  during  fermentation.  And  in  the  third  place 
it  prevents  putrifaction  setting  up. 

The  proportion  of  water  required  for  every 
280  lbs.  of  flour  is  from  25  to  30  gallons.  The 
water  should  first  be  carefully  measured  into  the 
flour  beck,  and  the  chloride  of  zinc  to  4  gallons 
at  102°  Twaddell  to  a  pack  of  280  lbs.),  added. 
The  flour  is  then  placed  in  the  mixture  of  water  and 
chloride  of  zinc,  and  agitated  till  ready  for  use.  It 
is  then  pumped  into  another  beck,  which  is  used  for 
the  storage  of  flour  which  has  previously  been  got 
ready  for  use.     In  preparing  a  "mixing,"  the  flour 


278      The  Chemistry  and  Practice  of  Sizing. 

should  be  taken  from  the  second  beck,  care  being 
taken  that  the  contents  are  well  agitated  previous 
to  running  any  out. 

Care  must  be  taken  not  to  use  too  large  a 
proportion  of  water  per  pack  of  flour,  otherwise  the 
mixed  flour  will  be  too  thin.  The  effect  of  this 
condition  would  be,  that,  if  the  agitators  were  allowed 
to  stop  for  a  lengthy  period,  the  starch  in  the  flour 
would  settle  to  the  bottom  of  the  beck  in  a  hard 
mass.  The  authors  know  of  cases  where  it  has 
been  necessary  to  run  off  the  top  water,  and  then 
dig  the  greater  portion  of  the  hard  mass  of  starch 
away  from  the  agitators  with  a  spade  before  the 
latter  could  be  moved. 

Measuring  the  Mixed  Flour. — Opinions 
amongst  sizers  differ  considerably  as  to  the  best  way 
of  dealing  with  the  flour  in  steep  when  making  a 
mixing.  It  is  a  very  common  practice  to  calculate 
the  proportion  of  the  mixture  of  flour  and  water  to 
be  used  in  a  " mixing"  by  taking  the  specific  gravity 
or  Twaddell  of  the  mixture.  This  is  an  unscientific 
and  unsatisfactory  way  in  every  respect  and  it  leads 
to  variation  in  the  results, 

Twaddells,  or  hydrometers,  are  intended  to 
indicate  the  specific  gravity  of  liquids,  but  a  mixture 
of  water,  chloride  of  zinc,  and  flour,  is  not  a  liquid 
in  the  true  sense,  and  the  strength,  as  indicated  by 
the  Twaddell,  may  be  misleading  owing  to  the  fact 
that  the  flour  will  gradually  Twaddell  a  less  number 


Measuring  Strength  of  Flour.  279 


of  degrees  as  it  gets  more  broken  up.  The  time 
required  to  thoroughly  break  up  the  flour  depends 
upon  several  factors,  viz.  : — The  nature  of  the  flour, 
the  amount  of  water  which  is  added  to  it,  and  the 
amount  of  agitation  which  is  employed.  It  will  be 
readily  seen  therefore,  that  taking  the  strength  of  the 
flour  mixture  by  "Twaddelling"  is  most  misleading 
and  unsatisfactory. 

If,  instead  of  trying  to  bring  the  mixture  of  flour 
and  water  to  any  particular  Twaddell,  the  mixture 
was  made  in  such  a  way  that  a  given  volume  of 
it  represented  a  definite  weight  of  the  original 
solid  flour,  the  "mixings"  would  be  much  more 
uniform. 

The  correct  method  to  adopt  is  to  find  out 
exactly  what  depth  of  water  in  inches  should  be 
run  into  the  beck  per  pack  of  flour  (280  pounds). 
This  can  easily  be  ascertained,  either  by  pouring 
the  required  number  of  gallons  of  water  per  pack  of 
flour  into  the  beck,  and  making  careful  measure- 
ments of  the  increased  depth  by  means  of  a  rod,  or 
by  calculation  from  the  capacity  of  the  beck.  Thus, 
length  x  breadth  x  depth  will  give  capacity  in,  say, 
cubic  inches  ;  and  1,728  cubic  inches  =  6^  gallons. 
The  increase  in  depth  is  then  multiplied  by  the 
number  of  packs  of  flour  it  is  intended  to  put  down. 
When  the  amount  of  water  required  is  known,  the 
full  quantity  may  be  easily  and  accurately  measured 
as  follows  :  —  The  agitators  are  first  stopped  and  the 


280      The  Chemistry  and  Practice  of  Sizing. 

movement  of  the  flour  allowed  to  cease.  A  long 
rod  is  then  placed  to  the  bottom  of  the  beck,  care 
being  taken  to  hold  it  perpendicularly.  The  portion 
which  has  been  immersed  will  be  covered  with  flour 
and  water.  A  distance  should  be  then  measured 
from  the  top  of  the  immersed  portion  equal  to  the 
amount  it  is  intended  to  add  to  the  height  of  the 
contents  of  the  beck.  At  this  point  a  nail  is 
knocked  into  the  rod  at  right  angles  to  it.  The  end 
of  the  rod  is  then  put  to  the  bottom  of  the  beck, 
and  water  is  run  in  until  the  height  indicated  by  the 
nail  is  reached. 

If  this  operation  be  carefully  carried  out  every 
time  the  flour  is  put  down  there  will  always  be  a 
measured  amount  of  water  to  a  known  weight  of 
flour,  and  every  gallon  of  the  mixture  will  represent 
a  known  weight  of  the  original  flour.  More  uniform 
results  will  be  obtained  in  this  way  than  by  placing 
an  unknown  quantity  of  water  in  the  beck  to  begin 
with,  and  afterwards  trying  to  get  a  uniform  strength 
by  adding  more  water  until  the  mixture  of  flour  and 
water  Twaddells  a  certain  number  of  degrees. 

When  a  large  number  of  packs  of  flour  are 
being  put  to  steep  in  the  beck  it  is  advisable  to 
allow  more  time  to  elapse  before  adding  each 
succeeding  pack,  than  where  a  few  packs  only  are 
being  put  down.  If  this  be  done  it  causes  the  flour 
to  become  properly  mixed  much  sooner  than  if  there 
were  no  interval.    It  also  avoids  excessive  strain 


Treatment  of  Flour  in  Sizing.  2  8 1 


on  the  agitators  and  driving  strap.  Thus,  if  it  be 
intended  to  put  down  eight  or  ten  packs  of  flour,  it 
would  be  far  better  if  four  or  five  packs  were  mixed 
on  the  first  day,  two  more  on  the  second  day,  and 
one  more  on  each  succeeding  day,  than  if  the  whole 
of  the  flour  were  mixed  at  once. 

For  the  first  few  days  after  being  put  down  it  is 
evident,  from  the  appearance  of  the  contents  of 
the  beck,  that  the  ingredients  are  not  thoroughly 
mixed.  Each  succeeding  day  however,  the  mixture 
looks  thinner,  and  probably  in  a  week  or  ten 
days  it  will  have  a  limpid  appearance,  and  it 
will  splash  about  the  beck  wrhen  the  agitators  are 
rotating.  Previous  to  the  mixture  having  this 
appearance  it  is  not  advisable  to  move  the  flour 
from  the  first  beck,  and  nothing  will  be  lost  by 
keeping  at  least  a  few  weeks'  supply  in  the  second 
beck. 

Treatment  of  the  Various  Starches. — The 
pure  starches,  such  as  farina,  sago,  maize  and  rice, 
require  no  special  treatment.  There  is  no  necessity 
to  steep  or  ferment,  and  all  necessary  details  have 
been  given  in  the  first  chapter  of  the  book. 

Treatment  of  China  Clay. — The  method  of 
treating  China  clay  has  already  been  described. 
The  question  of  boiling  China  clay,  and  the 
advantages  of  using  powdered  China  clay,  have 
been  fully  dealt  with  on  pages  151  to  154.  Until 
powdered  clay  can  be  obtained  as  easily  as  the 


282        The  Chemistry  and  Practice  of  Sizing. 


present  form,  the  question  of  boiling  must  be 
considered. 

The  time  required  for  boiling  clay  depends 
largely  upon  the  work  for  which  it  is  intended. 
As  the  only  object  of  boiling  is  to  separate  the 
particles  of  clay,  the  time  occupied  "by  this  process 
depends  upon  whether  the  ''mixing"  be  a  "light"  or 
a  "heavy  "  one. 

For  "light"  sizing,  where  a  large  quantity  of 
water  can  be  used  to  a  small  amount  of  clay,  it  is 
not  necessary  to  boil  for  more  than  an  hour.  In 
heavy  "sizing,"  where  the  quantities  are  reversed, 
the  clay  should  be  boiled  for  at  least  three  or  four 
hours,  otherwise  the  particles  do  not  get  separated 
sufficiently  to  produce  good  work. 

Chloride  of  Magnesium. — This  substance  is 
bought,  as  a  rule,  in  the  solid  state.  To  make  a 
solution,  a  hole  is  bored  in  the  cask,  and  a  small 
pipe  inserted,  through  which  steam  is  passed,  and, 
as  it  condenses,  the  chloride  of  magnesium  is 
dissolved.  The  solution  is  allowed  to  run  into  the 
beck  provided  for  its  reception,  This  beck  is 
generally  lined  with  lead,  to  prevent  the  contents 
percolating  through  the  wood.  The  solution  of 
chloride  of  magnesium  should  be  brought  to  a 
definite  strength  as  indicated  by  the  Twaddell. 
This  varies  according  to  individual  ideas,  and 
may  range  from  50°  to  66°  Twaddell.  There  is 
no  one  particular  strength  which  is  more  conducive 


Method  of  Measuring  Chloride  of  Magnesium.  283 

to  good  work  than  another,  but  it  is  absolutely 
essential  that  the  Twaddell  should  be  the  same  for 
every  "mixing,"  otherwise  the  results  will  not  be 
uniform,  even  though  the  same  volume  has  been 
used.  It  is  not  advisable  to  prepare  chloride  of 
magnesium  solution  at  a  higher  Twaddell  than 
66°T,  as  above  this  strength  it  has  a  tendency  to 
crystallize  out  on  the  bottom  and  sides  of  the  beck. 
To  keep  the  strength  constant,  the  liquid  should  be 
Twaddelled  before  being  used,  care  being  taken 
that  the  contents  of  the  beck  have  been  well  agitated 
before  placing  the  hydrometer  into  the  liquid. 
The  Twaddell  should  always  be  taken  at  a  given 
temperature.  If  the  Twaddell  be  too  high,  water 
should  be  added  carefully  until  it  is  of  the  required 
specific  gravity. 

The  usual  method  of  measuring  the  solution  of 
chloride  of  magnesium,  when  making  a  "mixing,"  is 
generally  a  very  crude  one,  A  bucket  is  usually 
used  for  this  purpose.  If  the  exact  capacity  of  the 
bucket  be  known,  and  the  same  size  of  a  bucket  be 
used  every  time,  this  method  may  be  all  right,  but 
the  authors  prefer  to  have  an  ejector  fixed  at  the 
bottom  of  the  beck,  and  to  measure  the  quantity  of 
solution  required  in  inches,  by  means  of  a  rod  and 
nail  as  used  for  measuring  flour.  The  number  of 
gallons  per  inch  of  depth  may  be  easily  ascertained, 
and  from  this  data  the  quantities  may  be  calculated 
in  terms  of  inches.    By  this  method  it  is  impossible 


284       The  Chemistry  and  Practice  of  Sizing. 

for  the  size-mixer  to  forget  how  many  bucketfuls  he 
has  put  in  the  "  mixing  "  when  part  way  through  his 
work.  It  also  economises  labour,  and  at  the  same 
time  keeps  the  size-room  cleaner.  There  is  no 
possibility  of  spilling  the  chemical  on  the  floor,  as  is 
the  case  when  it  has  to  be  carried  from  one  beck  to 
another. 

The  authors  would  here  again  emphasise  the 
importance  of  making  measurements  with  the 
greatest  care. 

Chloride  of  Zinc. — The  method  of  mixing 
chloride  of  zinc  has  already  been  given  on  pages  81 
and  254.  The  size-mixer  should  record  in  a  book 
the  number  of  the  cask  and  the  date  on  which  it 
was  received.  He  should  also  record  in  this  book  the 
strength,  as  indicated  by  the  Twaddell,  of  the  first 
bucketful  drawn  from  every  cask.  This  is  a  most 
important  check,  and  it  becomes  a  valuable  record  if 
damage  should  occur  to  the  cloth  at  a  later  stage. 

METHOD  OF  MIXING  THE  SIZING 
INGREDIENTS. 

"Mixings"  are  generally  made  to  put  a  known  per- 
centage of  size  on  known  counts  of  yarn.  The 
right  proportions  of  the  various  ingredients  for  a 
certain  percentage  of  size  depends,  to  some  extent, 
upon  the  kind  of  cloth  it  is  intended  to  make. 
A  good  weaving  "mixing"  to  put  40  per  cent, 
of  size  on  a  "thin  sort,"  say  a  12  x  10,  would  not  be 


Method  of  Mixing  the  Sizing  Ingredients.  285 

suitable  to  put  the  same  per  cent,  of  size  on  the  same 
counts  of  yarn  for  a  20  x  20.  If  the  "  mixing  "  be 
suitable  for  the  "thin  sort,"  there  is  every  probability 
that  it  would  be  too  soft  for  the  "strong  sort,"  and 
vice  versa. 

The  proportions  of  the  ingredients  used  in  a 
"mixing"  vary  also  in  different  mills  for  many  other 
reasons.  In  the  first  place,  the  quality  of  the 
ingredients  affects  the  results.  In  the  second  place, 
the  proportions  may  vary  on  account  of  the  different 
treatment  they  receive  in  preparing  a  "mixing." 
For  instance,  a  "mixing"  not  previously  thoroughly 
boiled  before  being  used  by  the  taper,  would  require 
less  starchy  matter  than  one  boiled  for  a  few  hours. 
Again,  if  the  same  quantity  of  starchy  matter  be 
used,  the  "mixing"  which  has  not  been  boiled  will 
produce  a  harder  feeling  cloth,  and  one  more  free 
from  "dustiness,"  than  a  "mixing"  which  had  been 
boiled  through.  In  the  third  place  the  "feel" 
required  for  a  particular  cloth  has  to  be  taken  into 
consideration.  Thus  a  soft  smooth  "feel"  wTould 
require  a  slightly  different  "mixing"  from  that  re- 
quired for  a  rough  "grippy  feel,"  even  when  the 
percentage  of  size  is  the  same  in  each  case. 

The  authors  have  already  pointed  out  that  it 
is  almost  impossible  to  get  uniform  results  in  sizing 
where  it  is  the  practice  to  ascertain  the  strength  of 
a  mixture  of  flour  and  water  by  means  of  the 
Twaddell's  hydrometer.    This  objection  to  the  use  of 


286      The  Chemistry  and  Practice  of  Sizing. 

the  Twaddell  for  such  a  purpose  applies  even  more 
to  the  practice  of  trying  to  ascertain  the  strength  of  a 
completed  "mixing."  The  strength  of  the  "mixings'' 
for  a  certain  percentage  of  size,  as  indicated  by  the 
Twaddell,  may  vary  considerably  in  different  mills 
owing  to  the  difference  in  the  quality  of  the  ingredients 
used.  China  clay  affects  the  accuracy  of  the  Twaddell 
test  more  than  any  other  ingredient,  on  account  of 
the  variation  in  the  physical  characters  of  different 
clays.  The  Twaddell  should  be  confined  to  testing 
the  chlorides  of  magnesium  and  zinc,  and  the  strength, 
or  consistency  of  the  "mixing,"  should  be  kept 
uniform  by  weighing  all  the  solids  and  measuring 
all  the  liquids.  The  same  weights  should  be  put 
down  every  time,  and  the  liquids  (including  the 
water)  should  be  carefully  measured.  If  this  be  done 
better  results  will  be  obtained  than  if  the  "mixing" 
be  made  too  strong  in  the  first  place,  and  water 
afterwards  added  to  reduce  it  to  the  right  strength, 
as  indicated  by  the  Twaddell's  hydrometer. 

From  what  has  been  said,  it  will  be  obvious  that 
it  is  almost  impossible  to  have  a  mixing  which  would 
be  suitable  for  all  mills,  unless  the  ingredients,  and 
the  treatment  accorded  to  them,  were  exactly  the 
same.  Even  if  this  were  done  it  is  probable  that 
the  geographical  position  of  the  mill  might  entail 
slight  but  necessary  alterations.  A  mill  situated 
on  the  top  of  a  hill  would  require  a  slightly  different 
mixing  for  "heavy"  size  from  that  required  for 


Mixing  "Pure'  Size. 


287 


the  same  purpose  in  one  placed  in  a  valley,  and 
well  shielded  from  the  weather.  All  "mixings' 
given  in  books,  therefore,  should  be  used  as  a  basis 
only.  They  may,  and  probably  will,  especially  for 
"heavy"  sized  goods,  require  alterations  to  suit  the 
particular  conditions  under  which  the  cloth  has  to  be 
woven.  The  only  sure  rule  known  to  the  authors 
for  making  these  slight,  but  important  alterations 
correctly,  is  "the  rule  of  experience."  This  ex- 
perience can  be  obtained  by  making  alterations  in 
the  proportions  of  the  ingredients  of  a  14  mixing," 
and  carefully  observing  the  effects  produced  in  the 
weaving,  and  in  the  ''feel"  of  the  cloth.  If  there 
be  added  to  these  experiments  a  sound  general 
knowledge  of  the  properties  of  the  ingredients 
used,  there  should  be  no  difficulty  in  making  a 
suitable  mixing  for  any  class  of  sizing. 

Mixing  "  Pure  "  Size. — Mixing  "pure"  or 
" light"  size  is  a  very  simple  matter  compared  with 
mixing  "medium"  or  ''heavy"  size.  The  required 
quantity  of  water  should  be  placed  in  the  pan  or 
beck  in  which  it  is  intended  to  make  the  ''mixing." 
The  starch  and  tallow  are  afterwards  added  and  the 
mixture  is  heated  sufficiently  to  burst  some  of  the 
starch  granules.  This  causes  the  "  mixing"  to 
thicken  slightly,  and  in  this  condition  the  tallow  or 
wax  is  more  easily  incorporated.  The  starch  is 
also  prevented,  by  this  partial  gelatinization,  from 
settling  to  the  bottom  of  the  beck. 


288      The  Chemistry  and  Practice  of  Sizing. 

Another  method  which  is  sometimes  adopted,  is 
to  boil  the  " mixing"  until  it  becomes  thin  enough 
to  pass  through  the  pump,  This  method  un- 
doubtedly gives  a  softer  "feel"  to  the  cloth,  and 
more  pliability  to  the  yarn,  but  it  is  not  advisable  to 
treat  all  "pure"  size  mixings  in  this  manner.  For 
instance,  this  treatment  would  be  objectionable 
for  a  mixing  consisting  principally  of  farina. 
It  has  been  frequently  stated  that  farina  loses  its 
adhesiveness  to  a  greater  extent  than  any  other 
starch  by  prolonged  boiling,  and  such  treatment 
would  have  disastrous  results  in  the  weaving  shed 
when  the  yarn  came  to  be  woven.  There  are  other 
objections  to  boiling  a  "mixing"  in  bulk  before  it  is 
pumped  to  the  taper.  These  will  be  discussed  under 
"medium"  and  "heavy"  size. 

Mixing  "Medium"  and  "Heavy"  Size, — The 
method  to  be  adopted  in  mixing  "medium''  and 
"heavy  "  size  differs  somewhat  from  that  employed 
for  "light"  size.  In  the  first  place  there  are  more 
ingredients  to  consider,  and  in  the  second  place  they 
require  different  treatment.  The  following  procedure 
may  be  usually  adopted : — The  necessary  amount  of 
water  should  first  be  put  into  the  mixing  beck  or 
pan.  Afterwards  the  China  clay  should  be  added 
and  the  chloride  of  magnesium.  (In  the  case  of 
"heavy"  size  it  is  necessary  to  boil  the  chloride  of 
magnesium  with  the  clay  because  the  proportion  of 
water   available    to   boil  the  clay  is  small).  In 


Method  of  Mixing  the  Size.  289 


4 'medium  mixings"  it  is  not  necessary  to  add  the 
chloride  of  magnesium  until  the  clay  has  been 
boiled.  These  ingredients  are  then  boiled  for  a 
period  varying  from  one  to  four  hours,  according  to 
the  class  of  mixing;  longer  boiling  being  required 
for  the  "heavier  mixings"  than  for  the  "lighter 
mixings  "  in  order  to  bring  about  the  separation  of 
the  particles  of  clay. 

After  the  mixture  of  water  and  clay,  etc.,  has 
been  boiled  the  necessary  length  of  time  the  tallow 
should  be  added,  and  the  whole  boiled  for  a  few 
minutes.  In  the  meantime,  the  flour  should  be  run 
from  the  flour  beck  into  the  mixing  beck,  the  latter 
beck  being  arranged  immediately  under  the  clay 
pan.  When  the  China  clay  has  cooled  sufficiently 
to  allow  its  admixture  with  the  flour  it  is  run  into 
the  mixing  beck  and  thoroughly  mixed  with  the 
flour.    This  completes  the  "mixing." 

If  it  be  necessary  to  add  blue  to  the  "mixing," 
or  to  otherwise  alter  the  colour  of  the  size,  the 
requisite  amount  of  colouring  matter  should  be 
introduced  at  this  stage,  and  the  "mixing"  agitated 
until  it  is  required  by  the  "taper." 

The  amount  of  time  elapsing  between  the  making 

of  a  "mixing"  intended  for  "medium"  and  "heavy" 

sized  goods,  and  its  use  in  the  tape-frame,  may 

make    a    difference  in  the   weaving,  and   in  the 

general  appearance  of  the  cloth.    Where  there  are 

a  sufficient  number  of  becks  to  allow  a  few  days,  or 
s 


290       The  Chemistry  and  Practice  of  Sizing, 


even  a  week,  to  elapse  between  the  making  of  a 
"mixing''  and  its  use,  the  ingredients  get  worked  up 
finer,  and  the  whole  mass  is  more  uniform.  This 
tends  to  produce  a  better  looking  and  more  uniform 
cloth,  and  one  with  a  smoother  "feel"  than  would 
be  the  case  if  the  "mixing"  were  used  immediately 
after  being  made. 

It  has  been  mentioned  under  the  mixing  of 
"pure"  size  that  it  is  customary  in  some  mills  to 
boil  the  size  in  the  mixing  beck  before  going  to  the 
taper.  It  is  not  always  convenient  to  boil  "medium" 
or  "heavy"  size  sufficiently  thin  to  enable  it  to  be 
pumped  to  the  sow-box  because  the  size-mixing 
plant  is  not  always  adapted  for  it.  But  where  the 
plant  is  suitable,  and  the  boiling  is  done  in  the  right 
way,  there  is  no  question  that  better  results  are 
obtained  in  every  way.  In  the  first  place  the  yarn 
is  rendered  more  pliable,  thus  producing  better 
weaving.  In  the  second  place  the  cloth  has  a  much 
better  appearance  when  woven  than  it  would  have 
if  the  size  were  simply  boiled  in  a  small  enclosed 
pan  attached  to  the  tape-frame  previous  to  being 
boiled  in  the  "sow"  box. 

Some  of  the  chief  advantages  to  be  gained  by 
thoroughly  boiling  a  "mixing"  and  completely  gela- 
tinising the  starch  granules  are  as  follows  : — In  the 
first  place  the  starch  is  divided  into  minute  particles, 
in  which  state  it  can  be  intimately  mixed  with  the 
other  ingredients  of  the  size.    In  the  second  place, 


Method  of  Boiling  the  Size. 


291 


starch  which  has  been  completely  gelatinised 
prevents  to  a  great  extent  the  China  clay  from 
settling  out  and  sinking  to  the  bottom  of  the  beck. 
It  also  assists  in  keeping  the  tallow  or  wax  in  sus- 
pension, and  there  is  not  the  same  tendency  for  these 
substances  to  separate  out  and  float  on  the  surface 
when  the  "mixing"  cools.  Conditions  such  as  the 
above  all  make  for  uniformity  in  the  results  obtained 
in  sizing. 

It  may  be  as  well  to  point  out  at  this  stage  that 
some  of  the  starches,  such  as  sago,  rice,  and  maize, 
require  not  only  a  simple  boiling,  but  the  operation 
must  be  prolonged  sufficiently  to  cook  them, 
otherwise  the  best  results  cannot  be  obtained. 
On  this  account  it  is  necessary  to  continue  the 
boiling  of  these  starches  for  three  or  four  hours 
before  using  them. 

When  conducting  the  boiling  operations  for  a 
large  "mixing"  it  is  never  advisable  to  attempt  to 
boil  the  whole  mass  at  once.  If  this  were  attempted 
the  granules  of  the  starchy  matter  would  be  too 
rapidly  gelatinised,  and  the  probability  would  be 
that  the  agitators  in  the  beck  would  be  stopped 
on  account  of  the  "mixing"  becoming  converted 
into  a  solid  mass.  The  proper  method  to  adopt  in 
boiling  is  the  following: — A  portion  of  the  "mixing," 
say  about  a  foot  in  depth,  should  be  pumped  into  the 
pan  or  beck  in  which  it  is  intended  to  be  boiled. 
This  should  be  first  boiled  until  it  is  thin  enough 


292      The  Chemistry  and  Practice  of  Sizing. 

to  allow  the  agitators  to  revolve  at  their  normal 
speed.  The  remainder  of  the  mixing  should  then 
be  pumped  into  it.  If  a  good  supply  of  steam  has 
been  arranged  to  the  boil  pipe  the  size  will  be 
boiled  as  fast  as  it  is  pumped  into  the  beck. 

Although  it  is  advisable  to  boil  all  "  mixings " 
through  before  going  to  the  taper,  this  is  sometimes 
inconvenient,  owing  to  the  variety  of  sized  goods 
manufactured.  In  a  mill  where  only  two  or  three 
sorts  of  size  are  used,  and  these  are  of  a  "  light"  or 
''medium"  nature,  it  is  possible  to  carry  out  this  oper- 
ation, but  where  a  large  variety  of  sized  goods  are 
produced,  each  having  their  distinctive  weights 
and  "  feels,"  it  is  much  more  convenient  to  have  a 
good  form  of  boiling  pan  attached  to  the  tape-frame, 
This  point  will  be  further  discussed  in  the  chapter 
on  "tapeing." 

A  constant  source  of  trouble  to  be  guarded 
against  is  the  tendency  of  boiled  size  to  block  up  the 
pipes,  or  settle  in  a  hard  mass,  if  allowed  to  remain 
motionless  for  a  few  hours.  This  may  be  prevented, 
in  the  first  place,  by  means  of  a  pump  sufficiently 
large  to  keep  a  good  flow  of  size  through  the  pipes 
during  working  hours.  A  3-inch  pump  with  a  7-inch 
lift  would  be  suitable  for  this  purpose.  In  order  to 
prevent  the  size  settling  in  the  pipes  when  the  pump 
is  not  working,  as  during  meal  hours,  and  at  night, 
steam  should  be  forced  through  them,  For  this 
purpose  a  ^-inch  steam  pipe  should  be  coupled  to 


Size  "Mixings"  for  Various  Weights.  293 


the  "size"  pipe,  between  the  beck  tap  and  the  pump. 
The  pipes  can  thus  be  emptied  of  their  contents  by 
stopping  the  pump,  and  turning  on  the  steam.  This 
will  first  force  the  size  back  into  the  beck.  The  beck 
tao  should  then  be  shut,  when  the  size  will  be  forced 
along  the  pipes,  to  the  "  tape-frame,"  and  the  over- 
flow, and  thus  the  pipes  will  be  entirely  emptied. 

SIZE  "MIXINGS"  FOR  VARIOUS 
WEIGHTS. 

As  previously  stated,  it  is  not  possible  to  lay 
down  "mixings"  for  any  given  weight  of  size  which 
will  be  suitable  for  all  conditions.  The  "mixings" 
here  given  are  practical  working  recipes,  but  they 
should  be  used  as  a  basis  only. 

In  every  case  where  flour  is  mentioned  it  is 
assumed  that  this  ingredient  has  been  mixed  and 
steeped  with  chloride  of  zinc  in  the  proportion  of 
3^  to  4  gallons  for  each  280  pounds  of  flour  used. 

In  "pure"  sizing  the  strength  of  the  size  will 
depend  upon  the  fineness  of  the  reed,  the  number 
of  picks  it  is  intended  to  put  in  the  cloth,  and  the 
counts  of  yarn,  both  twist  and  weft.  The  strength 
will  vary  also  according  to  the  kind  of  cloth  it  is 
intended  to  weave.  Thus,  a  heavily  picked  plain 
cloth  will  require  a  greater  percentage  of  size  on 
the  yarn  than  a  twill  or  a  sateen  with  the  same 
number  of  picks,  owing  to  the  difference  in  the 
interlacing  of  the  warp  and  w7eft  threads. 


294      The  Chemistry  and  Practice  of  Sizing. 

In  making  alterations  in  the  strength  of  a  "pure 
mixing"  it  may  be  taken  as  a  general  rule,  that, 
with  a  given  weight  of  starchy  matter,  the  proportion 
of  softener  (tallow,  wax,  or  soap)  will  have  to  be 
increased  if  a  less  quantity  of  water  be  used  in  order 
to  make  a  stronger  "mixing."  To  illustrate  this 
more  fully,  suppose  "mixing"  No,  2  was  giving 
satisfactory  results  for  a  16  x  14  cloth  with  160 
gallons  of  water,  and  12  pounds  of  tallow,  and  the 
taper  required  a  set  of  beams  for  a  22  x  20  "sort." 
If  the  "  mixing"  were  not  altered  the  stronger 
"sort"  would  be  too  soft.  To  avoid  this  a  "mixing" 
would  have  to  be  made  with  the  same  weight  of 
starch,  but  with  130  gallons  of  water,  and  20  or  25 
pounds  of  tallow. 

The  method  of  mixing  the  size  will  cause 
variations  in  the  quantity  of  water  required.  If  the 
"mixing"  be  simply  heated  until  a  portion  of  the 
starch  granules  burst  more  water  may  be  used  to  a 
given  weight  of  starchy  matter  than  if  the  "mixing" 
be  boiled  for  three  or  four  hours,  previous  to  its 
being  used  by  the  taper.  In  the  latter  case  an 
allowance  must  be  made  for  the  extra  water  caused 
by  condensation  during  the  period  of  boiling.  Not 
only  must  an  allowance  be  made  for  the  quantity  of 
water,  but  the  amount  of  tallow  or  other  softener 
can  be  reduced  in  "mixings"  which  have  been 
subjected  to  a  prolonged  boiling. 

The  quantity  of  water  given  in  the  "mixings"  on 


Method  of  Boiling  the  Size, 


295 


page  296,  et  seq.,  allows  for  rather  more  than  the 
average  amount  of  condensation  of  steam  in  the  size- 
mixing  beck  and  in  the  "sow"  box. 

It  is  impossible  to  give  the  exact  quantity  of  water 
for  a  "mixing,"  owing  to  the  number  of  practical 
details  which  may  cause  it  to  vary  in  different  mills. 
This  can  be  ascertained  only  by  practical  experience. 
For  instance,  to  put  on  a  given  percentage  of  size 
the  quantity  of  water  required  for  a  "mixing" 
where  soft  spun  mule  yarn  is  being  used  would 
have  to  be  decreased  if  a  change  were  made  to 
ring  spun  yarn.  Again,  more  water  could  be  put 
to  a  "mixing"  in  a  mill  where  the  size-mixing 
apparatus  and  the  slashing  machine  were  in  close 
proximity  to  the  boiler  than  where  the  sizing 
operations  are  a  considerable  distance  away  from  the 
steam  supply.  In  the  latter  case  there  would  be  a 
very  large  amount  of  condensation  on  account  of 
the  greater  distance  the  steam  has  to  travel 
before  being  used.  When  the  steam  has  to  travel 
through  a  long  range  of  piping  it  is  advisable 
to  have  the  pipes  covered  with  some  substance 
which  is  a  non-conductor  of  heat.  In  this  way  a 
large  amount  of  condensation  is  prevented.  It  is 
also  advisable  to  insert  some  form  of  steam  trap  or 
separator  as  near  to  the  tape  frame  as  convenient. 
This  will  eliminate  a  large  proportion  of  the  con- 
densed steam,  and  thus  prevent  the  size  being 
weakened 


296      The  Chemistry  and  Practice  of  Sizing. 

Another  factor  which  may  cause  a  variation  in  the 
amount  of  water  required  for  a  "mixing"  is  the  weight 
of  the  finishing  roller.  If  a  change  were  made  in 
this  roller,  and  the  weight  were  increased  from  360 
to  480  pounds,  it  would  be  necessary  to  reduce  the 
quantity  of  water  used  in  the  "mixing."  This  is 
because  a  heavy  roller  will  squeeze  more  of  the  size 
from  the  yarn  than  a  light  one,  and  to  compensate 
for  this  the  size  must  be  made  stronger.  It  may  be 
as  well  to  state  here  that  a  heavy  finishing  roller, 
with  the  "size"  of  the  right  strength,  will  give  a 
better  appearance  to  the  wToven  cloth  than  can  be 
obtained  with  a  light  roller. 

The  following  "mixings"  are  based  upon  the  use 
of  a  standard  flour  and  a  standard  China  clay,  and 
any  deviation  from  these  ingredients  must  be 
allowed  for  :— 

No.  1 — "  Pure  "  Size. 


Water  

Tallow  or  Wax   

Farina  

Chloride  of  Zinc,  io2°T 
Caustic  Soda,  7o°T  ...  . 


120  to  180  gallons. 
to  to    30  pounds 

  224  pounds. 

  2  gallons. 


2  pints. 


No.  2— "Pure"  Size. 


Water. 
Tallow 
Farina. 
Sago  . 


1 10  to  160  gallons. 
10  to    30  pounds. 

  112  pounds. 

  112  pounds. 


Caustic  Soda,  7o°T 


2  pints. 


The  use  of  chloride  of  zinc  to  "  pure  mixings"  is  optional:  but  when 
it  is  omitted,  the  yarn  should  be  more  highly  dried  in  the  tapeing. 


Size  "Mixings." 


297 


The  addition  of  glycerin  to  the  "pure"  size  "mixings"  will  improve  the 
weaving,  but  if  the  goods  are  intended  for  shipment  in  the  grey  state,  it 
will  be  desirable  to  add  either  chloride  of  zinc  or  salicylic  acid,  in  order 
to  prevent  mildew  developing  during  transit  to  the  East.  If  salicylic  acid 
be  employed  as  the  antiseptic,  it  should  be  used  in  the  manner  described 
on  page  257,  and  in  the  proportion  of  6  ounces  to  every  100  pounds  of 
starch. 


No.  3 — Mixing  for  30  to  40  per  cent. 

Water   90  gallons. 

Chloride  of  Magnesium,  6o°T...  6  gallons. 
China  Clay    224  pounds. 

(West  of  England  Stone  and  China  Clay  Co.'s 
Special  Super),  see  page  149. 

Tallow    30  pounds. 

Flour      280  pounds. 

(H.  Hibbert  &  Co.'s  3H  ),  see  page  86. 

The  flour  is  assumed  to  have  been  previously  steeped  with  the  necessary 
proportion  of  chloride  of  zinc. 


No.  4 — Mixing  for  45  to  60  per  cent. 

Water   140  gallons. 

Chloride  of  Magnesium  6o°T...     15  gallons. 

China  Clay    672  pounds. 

(West  of  England  Stone  and  China  Clay  Co.'s 
Special  Super)  see  page  149. 

Tallow   90  pounds. 

Flour   448  pounds. 

(H.  Hibbert  &  Co.'s  3H.),  see  page  86. 

Maize  Starch  (Corn  Starch)   112  pounds. 

Chloride  of  Zinc,  io2°T    2  gallons. 

The  chloride  of  zinc  here  mentioned  is  put  in  to  counteract  the  tendency 
of  the  starch  to  mildew ;  the  flour  having  been  steeped  with  chloride  of 
zinc,  as  mentioned  in  No.  3. 


298      The  Chemistry  and  Practice  of  Sizing. 
No.  5— Mixing  for  80  to  100  per  cent. 


Water   80  gallons. 

Chloride  of  Magnesium,  6o°T...  20  gallons. 
China  Clay    896  pounds. 

(West  of  England  Stone  and  China  Clay  Co.'s 
Special  Super),  see  page  149. 

Tallow    120  pounds. 

Flour   320  pounds. 

(IT.  Hibbert  &  Co.'s  3H.),  see  page  86. 

Farina  or  Maize  Starch    40  pounds. 

Chloride  of  Zinc,  io2°T   \  gallons. 


The  chloride  of  zinc  here  mentioned  is  put  in  to  counteract  the  tendency 
of  the  starch  to  mildew  ;  the  flour  having  been  steeped  with  chloride  of 
zinc,  as  mentioned  in  No.  3. 


No.  6 — Mixing  for  140  to  160  per  cent. 

Water   75  gallons. 

Chloride  of  Magnesium,  6o°T...    35  gallons. 

China  Clay  1792  pounds. 

(West  of  England  Stone  and  China  Clay  Co.'s 
Special  Super),  see  page  149. 

Tallow   230  pounds. 

Flour   340  pounds. 

(H.  Hibbert  &  Co.'s  3H.),  see  page  86. 

Maize  Starch     120  pounds. 

Chloride  or  Zinc    ij  gallons. 

The  chloride  of  zinc  here  mentioned  is  put  in  to  counteract  the  tendency 
of  the  starch  to  mildew ;  the  flour  having  been  steeped  with  chloride  of 
zinc,  as  mentioned  in  No,  3. 


As  previously  stated  the  above  mixings  should 
be  used  as  a  basis  only.  Modifications  may  have 
to  be  made  according  to  conditions  under  which  the 
cloth  is  woven  and   also   according   to  the  feel 


"Sizing"  for  Native  Dyeing.  299 


required  in  the  woven  cloth.  Many  other  mixings 
for  special  results  could  be  given,  but  unless  the 
exact  requirements  of  the  sizer  were  known  they 
might  lead  to  confusion  and  mistakes.  For  instance, 
at  the  present  time  there  is  a  great  demand  for 
cloth  for  native  dyeing.  This  cloth  has  to  be  fairly 
heavily  sized  and  it  must  take  dye  well.  The  dyeing 
operations  are  conducted  by  natives  principally  in 
India,  China  and  Egypt. 

For  a  long  time  no  one  seemed  to  know  exactly 
what  form  this  native  dyeing  took.  It  used  to  be 
reported  to  the  writer  that  the  cloth  was  dipped  "  in 
a  native  dye,"  and  that  some  cloths  took  the  dye 
better  than  others.  In  the  course  of  time,  the 
writer  found  that  the  dyeing  was  practically  confined 
to  indigo,  and  that  those  cloths  which  had  a  good 
reputation  for  taking  the  dye  well  contained  the 
least  amount  of  tallow. 

When  the  demand  for  this  special  cloth  first 
became  general,  manufacturers  seemed  to  have  an 
idea  that  it  was  simply  a  case  of  dipping  the  cloth 
into  a  mixture  of  indigo  blue  and  water,  and  that 
the  pigment  was  fixed  or  plastered  on  in  some 
mysterious  way.  As  a  matter  of  fact  the  natives  of 
India,  China  and  Egypt,  have  some  considerable 
knowledge  of  the  use  of  dye  stuffs,  an  art  which  has 
been  handed  down  from  past  generations,  and  their 
dyeing  process  is  more  or  less  like  the  processes 
adopted  in  this  country,  z>.,  the  indigo  is  reduced 


300       The  Chemistry  and  P7'actice  of  Sizing, 

and  brought  into  solution  and  afterwards  pre- 
cipitated in  the  fibre. 

It  is  impossible  to  get  ideal  conditions  for  dyeing 
heavily  sized  cloth,  as  the  size  resists  the  dye.  The 
principal  ingredient  which  affects  the  dyeing  of  such 
cloth  is  the  tallow  or  other  fatty  substance  which 
has  been  used  as  a  " softener,"  Grease  resists 
liquids  and  prevents  the  dye  liquor  penetrating  the 
fibre.  The  only  method  of  overcoming  the  difficulty 
is  to  use  the  minimum  quantity  of  tallow  or  other 
fatty  "softener."  At  the  same  time  it  must  be 
understood  that  this  will  affect  the  weaving.  Tallow 
is  not  put  into  a  mixing  for  the  sake  of  putting  it  in, 
and  generally  sizers  will  err  on  the  side  of  economy 
without  much  pressure. 

The  writer  has  laid  down  scores  of  mixings  in 
recent  years  to  meet  the  requirements  of  the 
merchants,  and  in  some  cases  mixings  have  been 
employed  which  did  not  contain  any  fatty  matter 
whatever.  In  all  cases  of  this  kind  the  writer  has 
warned  the  manufacturer  that  he  was  bound  to  have 
trouble  in  some  form  or  other  with  the  weaving. 
Not  only  is  the  weaving  not  good,  but  there  is  a 
danger  of  iron  staining  in  the  looms.  Although 
there  are  many  difficulties  to  contend  with  in  this 
class  of  goods,  it  is  possible  to  size  the  yarn  in  such 
a  way  as  to  obtain  the  best  possible  results  with  the 
minimum  of  risk.  At  the  same  time  it  would  be 
unwise  to  publish  mixings  broadcast  for  sizers  to 


"Size  Mixings'  which  Cause  Tendering.  301 

use  under  conditions  unknown  to  the  writer  because 
loss  and  damage  would  probably  occur,  and  this 
loss  would  be  attributed  to  the  mixing.  Cases  of 
this  kind  require  dealing  with  personally,  and  the 
writer  would  urge  upon  all  sizers  not  to  experiment 
in  this  matter  without  expert  advice,  as  the  possible 
loss  due  to  trying  to  avoid  the  expense  of  advice 
may  be  many  times  greater  than  any  possible  fee. 
Not  only  is  there  a  danger  of  loss  from  spoiled 
material,  but  there  is  also  the  far  greater  danger  of 
loss  in  reputation  with  the  merchants  at  home  and 
abroad. 

Size  Mixings  which  Cause  Tendering 
when  the  Cloth  is  Singed. 

Whilst  discussing  the  question  of  size  mixings 
the  authors  would  like  to  call  attention  to  the 
demand  which  is  being  made  at  the  present  time 
upon  manufacturers  of  cloth  intended  for  bleaching. 
Merchants  are  requesting  that  the  yarns  shall  be 
fairly  heavily  sized,  on  the  ground  that  the  cloth 
"finishes"  better.  This  is  an  absurd  contention, 
and  it  is  leading  to  many  claims  for  damages.  /;/ 
the  first  place  the  authors  state  distinctly  that  a  large 
proportion  of  size  does  not  improve  the  " finish " 
of  the  cloth  after  it  has  been  bleached,  and  in  the 
second  place  a  lai'ge  proportion  of  size  cannot  be 
put  on  the  yarn  without  the  use  of  chloride  of 
magnesium,  chloride  of  calcium,  or  chloride  of  zinc. 


302        The  Chemistry  and  Practice  of  Sizing. 

Manufacturers  who  have  met  the  requirements  of 
the  buyers  have  had  claims  made  against  them  for 
damage  caused  by  tendering  which  has  developed 
when  the  cloth  is  singed  previous  to  bleaching,  or 
they  have  had  claims  put  in  for  washing  the  cloth 
before  it  has  been  singed  because  the  bleacher  has 
found  chloride  of  magnesium,  etc,  present, 

It  should  be  understood  once  for  all  that  ordinary 
counts  of  yarn  cannot  be  sized  successfully  more  than 
20  per  cent,  without  the  use  of  deliquescents,  and 
manufacturers  will  be  well  advised  if  they  refuse  to 
accept  the  conditions  imposed.  If  a  merchant 
wants  more  than  20  per  cent,  of  size  on  the  yarn  for 
ordinary  counts  he  should  be  made  to  accept  full 
responsibility  for  all  damages  from  its  presence. 

With  regard  to  the  contention  that  the  cloth 
"finishes"  better  an  explanation  of  how  this  mistaken 
idea  has  crept  in  may  help  to  stop  the  trouble  in 
future.  Supposing  that  two  pieces  of  cloth  are  sent 
to  be  bleached  and  finished,  and  they  are  identical 
in  reed  and  pick,  and  in  counts  of  twist  and  weft. 
One  piece  is  sized  sufficiently  for  weaving  only 
whilst  the  other  contains  20  per  cent,  of  size  on  the 
twist.  The  heavier  sized  piece  will  be  fuller  and 
heavier  than  the  pure  sized  cloth  for  a  given 
length,  and  it  will  appear  to  be  of  greater  value. 
When  these  two  cloths  are  bleached  and  " finished" 
they  will  probably  be  returned  to  the  merchant 
about  loom  weight,  and  the  cloth  which  was  more 


Effect  of  Excess  of  Size  on  Bleaching.  303 

heavily  sized  originally  will  be  fuller,  and  have  a 
better  "  finished  "  appearance  than  the  lighter  sized 
piece.  If,  however,  the  latter  cloth  had  as  much 
"filling"  put  into  it  by  the  "finisher"  as  the  former 
it  would  have  the  same  feel  and  appearance.  The 
"finisher"  can  get  the  desired  effect  by  suitably 
"filling"  without  the  manufacturer  being  requested 
to  waste  material  which  has  to  be  entirely  removed 
before  the  cloth  can  be  properly  bleached.  In  the 
process  of  bleaching  not  only  is  the  added  size 
removed,  but  a  considerable  proportion  of  the 
natural  constituents  of  the  cotton  as  well,  otherwise 
the  bleaching  could  not  be  properly  carried  out. 
Merchants  are  asking  for  impossible  conditions 
when  they  require  the  yarn  to  be  sized  as  much  as 
30  per  cent,  and  upwards,  and  at  the  same  time 
request  that  no  substances  shall  be  used  which  may 
damage  the  cloth  when  it  is  "singed."  There  is  a 
limit  to  what  can  be  done  in  this  way. 

There  is  another  reason  why  merchants  are 
asking  for  cloth  to  be  extra  weighted  in  the  grey  state. 

A  great  deal  of  pure  sized  cloth  is  sent  abroad 
to  be  bleached  and  embroidered,  and  if  this  cloth  is 
not  above  a  certain  weight  for  a  given  length  and 
width  it  is  charged  duty  at  a  higher  rate  than 
if  it  conformed  to  a  certain  weight.  This  has  led 
merchants  to  ask  for  more  size,  the  only  use  of  which 
is  to  save  the  extra  duty.  Many  manufacturers 
have  overcome  the  difficulty  by  dusting  China  clay 


304       The  Chemistry  and  Practice  of  Sizing 

between  the  folds  of  the  cloth  as  it  has  been  lapped 
on  the  folding  machine. 

The  only  way  to  prevent  claims  for  damages  in 
cloth  which  has  to  be  bleached,  is  for  all  manu- 
facturers to  firmly  refuse  to  put  more  size  on  the 
yarn  than  is  required  for  weaving  unless  the  merchant 
will  accept  full  responsibility  for  conditions  altogether 
unsuitable  for  safety  and  good  weaving. 

COLOURS  USED   FOR  TINTING 
THE  SIZE. 

It  is  a  common  practice  to  tint  the  size.  This 
is  done  with  two  objects.  In  the  first  place  the 
operation  is  carried  out  in  order  to  reduce  the 
yellowish  tint  natural  to  cotton.  For  this  purpose 
blue  of  some  description  is  used.  In  the  second 
place  the  operation  is  carried  out  for  the  purpose 
of  giving  some  distinctive  tint  to  the  cloth.  In 
the  latter  case  the  object  is  generally  to  produce 
a  shade  on  American  cotton  similar  to  that  possessed 
by  Egyptian  cotton.  Sometimes  this  is  done  for 
the  purpose  of  deceiving  the  buyer,  but  very  often 
it  is  done  with  the  object  of  producing  a  cloth  with 
a  pleasing  shade  of  colour.  Not  only  is  tinting 
being  carried  out  for  the  purpose  of  imitating  the 
shade  of  Egyptian  cotton,  but,  at  the  present  time, 
it  is  being  largely  carried  out  for  certain  fabrics,  the 
yarns  of  which  were  formerly  dyed  previous  to 
sizing.     For  this  purposes  many  shades  of  greens, 


Colours  used  for  Tinting  the  Size.  305 


blues,  yellows,  etc.,  have  to  be  obtained,  A  list  of 
the  dyes,  from  which  most  of  the  tints  can  be 
obtained,  is  given  below. 

The  colours  generally  employed  in  tinting  are 
obtained  from  the  coal  tar  or  aniline  colours.  In 
some  cases  pigment  colours,  such  as  ultramarine 
blue,  yellow  ochre,  brown  umber,  and  the  chromate, 
and  oxychromate  of  lead,  are  used.  Occasionally 
indigo  blue  is  employed.  With  the  exception  of 
ultramarine  and  indigo,  these  colours  are  not  so 
suitable  as  coal  tar  colours  for  tinting  size. 

COAL  TAR  COLOURS. 
These  colours  may  be  divided  into  two  classes, 
viz.  : — basic  colours  and  substantive  colours,  the 
latter  being  known  as  "direct"  colours.  The 
following  is  a  list  of  the  principal  coal  tar  colours 
used  for  tinting  size  : — 


Basic  Colours. 

Substantive  or  "  Direct 
Cotton  Colours." 

Methylene  Blue. 

Benzo  Sky  Blue. 

Methyl  Violet. 

Diamine  Sky  Blue. 

Bismarck  Brown. 

Benzo-chrome  Brown. 

Auramine  Yellow. 

Chloramine  Yellow. 

Chrysoidine  Orange 

Mikado  Orange. 

Saffranine. 

Fast  Benzo  Red  4B. 

Geranine  Pink. 

Erica  Pink. 

Basic  Colours. — These  colours  fade  much 
more  rapidly  under  the  action  of  light  than 
substantive  colours. 

T 


306      The  Chemistry  and  Practice  of  Sizing, 

The  various  basic  colours  here  mentioned 
are  employed  for  the  following  purposes  : — 
Bismarck  brown  is  used  for  the  production  of  dark 
cream  shades  and  buffs.  It  is  used  also  for  imitating 
the  colour  natural  to  Egyptian  cotton,  but  when 
used  alone  it  does  not  give  very  good  results  for 
this  purpose,  Mixtures  of  auramine  yellow  and 
chrysoidine  orange  yield  any  shade  of  cream 
which  may  be  desired.  These  two  colours  when 
mixed  in  suitable  proportions  produce  a  shade  which 
is  a  very  good  imitation  of  Egyptian  cotton. 
Methylene  blue  and  methyl  violet  are  largely 
employed  for  the  purpose  of  reducing  the  yellowish 
shade  natural  to  cotton.  Care  should  be  taken 
when  selecting  a  blue  that  it  possesses  a  reddish 
shade.  The  red  has  the  power  of  neutralising  the 
natural  yellow  tint  of  the  cotton  and  produces  a  white 
effect,  whereas  some  blues  produce  a  greenish  shade 
in  the  cloth  which  is  very  objectionable.  Methylene 
blue  and  methyl  violet  are  also  employed  for  the 
purpose  of  giving  a  blue  tint  to  the  yarn. 

Basic  colours  may  be  dissolved  by  first  mixing 
the  dye  with  sufficient  water  to  form  a  paste,  after- 
wards adding  a  small  quantity  of  acetic  acid,  and 
finally  the  necessary  quantity  of  water.  The 
following  proportions  should  be  used  to  make  a 
standard  solution  : — 

Basic  Colour    4  ounces. 

Acetic  Acid    5  ounces. 

Water   1  gallon. 


Colours  used  for  Tinting  the  Size.  307 


Instead  of  acetic  acid  and  water,  methylated 
spirit  might  be  used  for  sizing  purposes. 

Substantive  Colours— Direct  Cotton  Dyes. 
These  colours  are  faster  to  light  than  the  basic 
colours,  and  they  are  with  difficulty  removed  by 
bleaching ;  in  fact,  it  is  impossible  to  discharge 
the  colours  entirely  without  destroying  the  cloth. 
Substantive  colours  should  be  used  always  in 
alkaline  solutions.  The  various  colours  given  in 
the  list  may  be  used  for  the  following  purposes  : — 
benzo  sky  blue,  and  diamine  sky  blue,  may  be  used 
for  producing  blue  tints,  or  for  reducing  the  yellowish 
shade  of  the  cotton.  Benzo-chrome  brown  may  be 
used  for  dark  creams  and  buffs.  Mixtures  of 
chloramine  yellow  and  Mikado  orange,  or  mixtures 
of  chloramine  yellow  and  benzo-chrome  brown,  will 
produce  any  desired  shades  of  cream.  These  latter 
colours  may  be  used  also  for  imitating  the  shade  of 
Egyptian  cotton,  a  subject  which  will  be  described 
on  page  311.  Various  shades  of  green  may  be 
obtained  by  mixing  the  blue  dyes  with  the  yellow 
and  orange  dyes. 

Substantive  colours  should  be  dissolved  by 
boiling  with  water  and  a  little  soda  ash  in  a  suitable 
vessel.  The  following  proportions  may  be  used  in 
order  to  make  a  standard  solution  : — 

Substantive  Colour    8  ounces. 

Soda  Ash    8  ounces. 

Water    1  gallon. 


308       The  Chemistry  and  Practice  of  Sizing. 

Method  of  Mixing  the  Colours  with 
the  Size. 

The  solution  of  dye  should  be  strained 
through  a  fine  cloth  previous  to  being  mixed  with 
the  size.  The  colour  is  run  into  the  ''mixing,"  as 
described  on  page  289. 

It  is  important  to  remember  that  on  no  account 
should  basic  and  substantive  colours  be  mixed. 
They  are  diametrically  opposed  to  each  other  in 
properties,  and  will,  on  being  brought  together  in 
solution,  precipitate  each  other.  Cases  are  not 
unknown  where  colour  dealers  have  sold  basic 
colours  and  substantive  colours  to  manufacturers 
to  be  used  together  to  produce  a  certain  shade.  In 
some  cases  the  right  tint  has  been  obtained  with  such 
mixtures  of  dyes,  so  long  as  the  size  "mixing"  was 
cold,  but  as  soon  as  it  was  boiled,  a  different  shade 
altogether  was  produced. 

ULTRAMARINE  BLUE. 

This  pigment  is  a  mineral  colour  and  is  produced 
by  heating  together  in  certain  proportions  China 
Clay,  sulphate  of  soda,  charcoal,  and  sulphur.  The 
honour  of  having  produced  ultramarine  falls  to 
Grumet  and  Gmeling.  These  chemists  devised 
methods  for  its  manufacture  independently  of  each 
other.  Previously  it  was  prepared  from  the  precious 
stone  lapis  lazuli,  which  was  ground  to  a  fine  powder 
and  used  for  painting,  but  its  price  was  very  high. 


Colours  used  for  Tinting  the  Size, 


Ultramarine  is  produced  in  two  distinct  stages  : — 
i  st. — The  preparation  of  green  ultramarine. 
2nd. — Conversion  into  blue  ultramarine. 

In  the  first  operation  the  China  clay,  charcoal, 
and  sulphate  of  soda,  are  well  ground  together,  and 
then  ignited  in  a  suitable  furnace.  A  white  mass 
is  produced,  which,  on  exposure  to  the  air,  becomes 
green.  The  blue  ultramarine  is  produced  by  roast- 
ing the  green  product  with  sulphur  at  a  low  tem- 
perature in  contact  with  the  air.  The  conduct  of  all 
the  operations  requires  great  care  and  skill. 

Ultramarine  is  not  affected  by  light,  air,  or 
alkalies,  but  acids  rapidly  discharge  the  colour,  at 
the  same  time  liberating  the  nauseous  smelling  gas 
sulphuretted  hydrogen. 

Ultramarine  is  frequently  adulterated.  The  best 
method  of  judging  the  quality  of  a  sample  is  to 
compare  its  colour  with  a  standard  sample.  The 
substances  used  for  the  adulteration  of  ultramarine 
are  finely-powdered  glass  and  sulphate  of  barium. 
Both  substances,  but  especially  the  sulphate  of 
barium,  reduce  the  tinting  power  of  the  blue. 

Use  of  Ultramarine  Blue  in  Sizing. — This 
blue  is  one  of  the  best  for  reducing  the  yellowish 
shades  of  cotton.  It  does  not  deteriorate  on  ageing. 
The  method  which  should  be  employed  for  mixing 
the  colour  is  as  follows: — A  standard  mixture 
is  prepared  by  mixing  one  pound  of  blue  with 
one   gallon    of  water.       The   water   should  be 


3  io      The  Chemistry  and  Practice  of  Sizing. 

added  gradually,  just  sufficient  at  first  to  form 
the  colour  into  a  thick  smooth  paste.  The  rest 
of  the  water  is  then  stirred  in.  On  no  account 
should  the  ultramarine  blue  and  water  be  boiled 
together.  Boiling  causes  the  solid  particles  of  the 
colour  to  settle  out.  Some  sizers  add  acid,  such  as 
hydrochloric  or  sulphuric  acid,  to  the  mixture  of 
ultramarine  and  water,  with  the  view,  as  they  say, 
of  bringing  the  colour  into  solution.  It  has  been  stated 
previously  that  acids  decompose  this  colour,  and 
all  that  goes  into  solution  is  that  which  has  become 
decomposed,  and  which  has  in  consequence  entirely 
lost  its  colour.    Such  a  method  is  very  objectionable. 

Ultramarine  blues  differ  considerably  in  shade 
of  colour.  Those  most  suitable  for  producing  a 
oood  tint  have  a  reddish  shade.  This  more 
readily  disguises  the  faint  yellow  tint  possessed 
by  the  cloth. 

INDIGO  BLUE. 

This  substance  is  one  of  the  most  important 
colours  used  in  printing  and  dyeing,  possessing  as  it 
does  the  most  valuable  of  all  qualities — fastness. 
Indigo  Blue  is  rarely  used  for  tinting,  and  only  when 
specially  requested.  It  should  be  ground  into  a  paste 
with  lime  water  in  a  suitable  mill.  This  paste  is 
further  diluted  with  water  and  strained  through  a 
fine  cloth  before  being  added  to  the  mixings. 


Tinting  Egyptian  Shades.  3 1 1 


Indigo  is  a  derivative  of  plants  of  the  family  of 
Papilionacoe,  of  different  species  of  indigofera,  which 
grow  in  India,  China,  etc.  One  of  the  most 
valuable  properties  of  indigo  is  that  it  can  be 
converted,  by  reduction,  into  indigo  white,  a  body 
which  is  soluble  in  weak  alkaline  liquids.  If  a 
fibrous  material  be  immersed  in  a  bath  of  reduced 
indigo  white  solution,  it  absorbs  this  substance, 
which  by  exposure  to  air,  is  re-oxidised  to  indigo 
blue,  thereby  rendered  insoluble  and  fixed  per- 
manently in  the  fibre.  Artificial  indigo  may  be 
substituted  for  natural  indigo  with  advantage. 

TINTING   EGYPTIAN  SHADES. 

The  colours  used  for  producing  the  shade  of 
Egyptian  cotton  on  American  yarns  have  already 
been  mentioned.  These  colours  require  using  with 
very  great  care,  as  many  cases  of  damage  have 
been  caused  by  manufacturers  using  dyes  which 
were  unsuitable  for  the  purpose.  A  great  deal 
depends  upon  the  treatment  the  cloth  is  to  be 
subjected  to  after  it  leaves  the  manufacturer.  If  it 
be  intended  to  be  sold  and  used  in  the  unbleached 
state,  then  mixtures  of  chloramine  yellow  and  benzo- 
chrome  brown  G.  are  suitable ;  the  quantities  and 
the  proportions  of  the  dyes  depending  upon  the 
shade  required,  and  upon  the  percentage  of  size  to 
be  put  on  the  yarn.  The  above  colours,  however, 
are    not   suitable    for   goods    which    have  to  be 


3 1 2      The  Chemistry  and  Practice  of  Sizing. 

bleached,  as  they  cannot  be  entirely  removed  in  the 
bleaching  operations.  After  bleaching,  the  cloth 
does  not  retain  the  same  shade  as  it  possessed 
before,  but  it  is  not  possible  to  get  a  white  cloth  if 
either  of  these  dyes  are  present.  Cases  are  not 
unknown  where  manufacturers  have  tinted  American 
twist  with  mixtures  of  benzo-chrome  brown  and 
chloramine  yellow  with  the  intention  of  deceiving 
the  merchant.  When  the  cloth  has  been  bleached 
the  weft  has  come  up  white  whilst  the  twist  has 
been  tinted.  The  consequence  of  this  is  that  the 
cloth  has  been  entirely  spoiled  for  the  purpose  for 
which  it  was  required. 

A  case  which  came  under  the  writer  s  notice,  and 
one  in  which  the  manufacturer  had  been  practising 
this  deception,  illustrated  the  maxim  that  a  little 
knowledge  is  a  dangerous  thing.  In  this  case  the 
manufacturer  was  making  a  satteen  cloth,  the  selvedge 
of  which  contained  cotton  and  worsted  twist.  The 
worsted  was  a  bleached  yarn,  and  it  was  introduced 
in  order  that  when  the  cloth  was  scoured,  i.e.,  half 
bleached,  and  afterwards  dyed  with  aniline  black, 
the  selvedge  would  have  the  appearance  of  a  check 
pattern.  This  is  possible  in  aniline  black  dyeing, 
because  the  woollen  fibre  does  not  "take"  the  dye 
in  this  process,  and  in  consequence  comes  up  white. 

The  manufacturer  was  under  the  impression  that 
those  colours,  known  as  substantive  colours,  wrould 
not  dye  wool  fast  shades,  and  concluded  that  if  he 


Tinting  Egyptian  Shades.  313 


used  this  class  of  colours  for  tinting  his  size  in 
order  to  get  the  shade  of  Egyptian  cotton  on  the 
twist  it  would  be  alright.  He  did  not  know  that 
many  of  the  substantive  colours  will  dye  wool, 
and  the  consequence  of  this  was  that  he  used 
benzo-chrome  brown  and  chloramine  yellow,  with 
the  result  that  wThen  the  goods  were  bleached,  the 
wool,  which  should  have  been  white,  came  up 
yellow.  It  would  not  have  mattered  in  this  case  about 
the  cotton  coming  up  yellow  after  bleaching,  as  the 
aniline  black  would  cover  it,  but  it  mattered  very 
considerably  about  the  worsted  having  a  yellow  tint. 
As  a  matter  of  fact  the  worsted  yarns  ought  never 
to  have  been  passed  through  a  tinted  size,  but 
should  have  been  sized  in  a  separate  "sow"  box. 

In  such  a  case  as  quoted,  where  worsted  yarns 
were  used  in  the  selvedge,  it  would  not  have  done 
to  have  used  any  of  the  basic  colours,  as  these 
colours  are  fast  on  woollen  fibres.  Basic  colours 
may  be  used  where  the  cloth  is  entirely  composed 
of  cotton,  and  where  it  has  afterwards  to  be 
bleached  white. 

As  previously  stated,  the  proportions  of  the  dyes 
required  for  giving  any  particular  shade  of  Egyptian 
cotton  depends  upon  the  amount  of  size  to  be  put 
on  the  yarn.  It  would  therefore  be  useless  to  give 
a  standard  mixture. 

It  is  necessary  to  call  attention  to  one  serious 
drawback  to  tinting  the  yarns  during  the  operation 


314      The  Chemistry  and  Practice  of  Sizing, 

of  sizing.  If  the  tape  frame  be  stopped,  a  larger 
quantity  of  dye  is  absorbed  by  the  yarn  where  it 
has  remained  in  longer  contact  with  the  size.  This 
will  show  as  a  brown  stain  across  the  piece  when 
the  cloth  is  woven.  This  difficulty  occurs  also 
when  the  tape  frame  is  run  on  the  slow  motion, 
although  the  depth  in  shade  is  not  so  marked  as 
when  the  machine  is  stopped  altogether. 

It  is  hardly  possible  to  avoid  this  objectionable 
result.  The  only  thing  to  do  would  be  to  raise  the 
yarn  from  the  size  when  the  machine  is  stopped  (if 
this  were  possible),  and  also  avoid  running  on  the 
slow  motion  as  much  as  possible. 


The  Tape  Frame. 


315 


Chapter  VIII. 

Tape-Sizing. 


THE  TAPE  FRAME. 

TAPE-SIZING  is  the  principal  method  used 
in  the  cotton  trade  for  incorporating  the  size 
with  the  yarn,  and  the  tape-frame,  or  slashing 
machine  {see plate xii.),  is  the  most  important  machine 
used  in  the  preparation  of  the  yarn  for  weaving.  It 
consists  of  the  following  principal  parts : — 

1.  The  Creel,  for  holding  the  back  beams. 

2.  The  "Sow"  Box,  wherein  the  size  is  boiled 

and  put  on  the  yarn. 

3.  The  Cylinders,  for  drying  the  sized  yarn. 

4.  The  Headstock,  which  is  made  up  of  a 

variety  of  motions  and  of  appliances,  the 
latter  of  which  are  used  for : — 
(a)  Cooling  the  yarn. 

{b)  Separating  the  threads  from  each  other. 
(c)  Marking  off  the  desired  length. 
{d)  Winding  the  yarn  on  a  beam  in  a  uniform 
sheet  of  the  required  width. 

The  Creel. 

The  creel  is  formed  from  two  duplicate  cast-iron 
frames  upon  which  are  bolted  the  beam  brackets. 
The  frames  are  bolted  together  with  wrought-iron 


3 1 6      The  Chemistry  and  Practice  of  Sizing. 

stay-rods.  The  beam  brackets  are  arranged  on  two 
levels,  so  that  the  first,  and  each  alternate  beam,  is 
on  the  lower  level,  whilst  the  second,  and  each 
alternate  beam,  is  on  the  higher  level.  Where  there 
is  sufficient  room  it  is  advisable  to  have  the  beam 
centres  a  fair  distance  apart  and  the  position  of  the 
even-numbered  beams  low.  This  arrangement  saves 
unnecessary  lifting  when  putting  in  a  "set,"  and 
at  the  same  time  prevents  the  upper  beams  over- 
hanging the  lower  ones. 

The  Size,  or  "Sow"  Box. 

The  size  or  "sow  "  box  may  be  constructed  from 
a  variety  of  materials.  Some  "sow"  boxes  are  made 
entirely  of  cast-iron,  whilst  others  are  constructed 
with  cast-iron  ends,  and  with  the  bottom,  front,  and 
back  made  of  pitch  pine.  Occasionally  this  form  of 
"sow"  box  is  lined  with  sheet  copper  in  order  to 
prevent  the  boiling  size  injuring  the  wood-work. 
Copper  linings  may  protect  the  wood-work  but 
there  is  always  the  danger  of  the  copper  being 
attacked  by  the  chemicals  in  the  size.  This  might 
be  more  objectionable  than  the  damage  to  the 
wood.  It  is  certainly  a  cause  of  irregular  shades  in 
the  colour  of  the  woven  cloth.  Where  a  copper 
lined  "sowT"  box  is  in  use  it  will  be  found  that  the 
size  which  had  been  left  in  the  box  overnight  is 
tinted  green,  and  the  authors  know  of  many  cases 
where  this  green  size  has  produced  a  distinct  green 


The  Size  or  "Sow"  Box. 


3i7 


shade  on  the  first  beam  of  a  day's  work.  The  chief 
source  of  this  trouble  is  the  presence  of  acid  in  the 
size.  This  may  be  due  either  to  rancid  tallow,  acid 
flour,  or  acid  in  the  chloride  of  zinc.  There  is  no 
doubt  that  a  copper  lined  "sow"  box  is  more  easily 
cleaned  than  a  wooden  one,  and  this  is  of  great 
advantage  where  it  is  the  practice  to  tint  the  yarns, 
a  practice  which  is  fairly  common  at  the  present 
day.  The  coloured  size  can  be  easily  cleaned  from 
a  copper  lined  "sow"  box,  whereas  if  a  wooden 
box  be  used  the  dye  is  certain  to  impregnate  the 
wood  and  it  can  be  entirely  removed  only  with 
difficulty.  If,  instead  of  using  copper  for  the  "sow" 
box  lining,  lead  or  zinc  were  employed  in  its  place, 
none  of  the  ill-effects  just  mentioned  would  be 
produced. 

There  are  many  different  opinions  as  to  the 
form  the  "sow"  box  should  take.  The  authors 
advise  the  use  of  a  deep  box  in  preference  to  a 
shallow  one.  The  former  holds  more  size  and  on 
this  account  permits  the  size  being  boiled  for  a 
longer  time  before  it  comes  in  contact  with  the  yarn. 
Another  advantage  is  that  the  steam,  issuing  from 
the  boil  pipes,  has  a  greater  distance  to  travel 
before  reaching  the  surface  of  the  size.  It  thus 
gives  up  more  of  its  heat  in  its  passage  through  the 
size  before  being  liberated  at  the  surface. 

The  "  sow  "  box  is  fitted  with  the  following 
essential  parts  : — Feed  Pipe,  Boiling  Pipes,  Float 


3 1 8        The  Chemistry  and  Practice  of  Sizing, 


Roller,  Immersion  Roller,  Copper  Roller,  Finishing- 
Roller,  Guide  Rollers,  and  Falling  Roller. 

The  Feed  Pipe. — The  feed  pipe,  which  should 
be  sufficiently  long  to  go  across  the  "sow"  box, 
should  be  placed  a  few  inches  from  the  bottom  and 
about  the  same  distance  from  the  back  of  this  box. 
It  should  be  perforated  at  equal  distances  with  a 
row  of  holes,  the  number  depending  upon  the 
class  of  sizing.  For  "pure"  sizing  6  holes  will  be 
sufficient  and  these  should  have  a  diameter  of  \  of 
an  inch.  For  "medium"  and  ''heavy"  sizing  from 
9  to  12  holes  of  varying  diameters  will  be  necessary. 
The  first  hole,  i.e.,  the  one  at  the  feed  end  of  the 
pipe,  should  have  a  diameter  of  \  of  an  inch,  as  for 
"pure"  sizing,  whilst  the  others  should  increase  in 
size  gradually  to  \  of  an  inch.  These  holes  should 
be  set  facing  downwards  and  backwards.  If  the 
feed  pipe  be  arranged  in  the  manner  described 
the  size  will  be  delivered  evenly  across  the 
"sow"  box,  and,  at  the  same  time,  as  far  as  possible 
away  from  the  place  where  it  comes  in  contact 
with  the  yarn. 

The  Boil  Pipes. — The  boil  pipes  are  constructed 
from  two  straight  copper  tubes  with  an  internal 
diameter  of  one  inch.  These  pipes  should  extend 
the  full  width  of  the  box,  Each  pipe  should  be 
fitted  with  a  separate  f-inch  tap  to  enable  the  taper 
to  regulate  the  amount  of  steam  to  his  requirements. 
In  many  cases  the  steam  is  supplied  to  one  end  of 


Sow"  Box — Boil  Pipes. 


319 


each  pipe  only.  This  arrangement  is  not  the  best 
as  it  tends  to  produce  a  variable  "boil"  owing  to 
the  steam  decreasing  in  pressure  as  it  gets  further 
away  from  the  supply.  A  better  way  is  to  extend 
each  boil  pipe  through  both  sides  of  the  "sow" 
box  and  to  couple  up  the  steam  supply  at  each  end. 

The  holes  in  the  boil  pipes  should  be  arranged 
in  two  rows.  If  the  boil  pipes  are  arranged  to  rest 
upon  the  bottom  of  the  box  the  two  rows  of  holes 
should  be  drilled  exactly  opposite  to  each  other,  and 
care  should  be  taken  that  the  pipes  are  so  fixed  that 
the  holes  are  set  in  a  direction  parallel  with  the 
bottom  of  the  box,  otherwise  one  row  of  holes  may 
be  facing  upwards,  and  the  other  downwards. 
This  would  cause  the  steam  issuing  from  the 
lower  row  to  quickly  blow  a  series  of  holes 
through  the  wood-work  of  the  "sow"  box,  unless 
it  were  lined. 

The  best  method  of  arranging  the  boil  pipes  is 
to  place  them  a  few  inches  from  the  bottom  of  the 
"sow"  box.  The  holes  can  then  be  drilled  below 
the  axis  of  the  pipe,  and,  although  both  rows 
of  holes  are  slightly  inclined  towards  the  bottom  of 
the  box,  there  is  not  the  same  danger  of  injuring 
the  wood-work  on  account  of  the  depth  of  size  which 
intervenes  between  the  exits  of  the  steam  and  the 
wood-work  of  the  box.  Another  advantage  of  this 
arrangement  is  that  there  is  not  the  same  tendency 
for  the  holes  to  get  made  up. 


320      The  Chemistry  and  Practice  of  Sizing. 

The  Float  Roller. — The  float  roller,  which 
is  connected  with  the  self-feed  valve,  is  used  for  the 
purpose  of  regulating  the  amount  of  size  entering 
the  "sow"  box.  It  consists  of  a  hollow  copper 
roller,  one  end  of  which  works  in  a  fixed  bracket, 
whilst  the  free  end  works  in  a  vertical  "guide." 
The  free  end  of  the  roller  thus  rises  and  falls 
according  to  the  depth  of  size  in  the  "sow"  box  in 
the  same  manner  as  the  "ball  float"  used  for 
regulating  the  water  supply  to  a  bath  cistern.  One 
end  of  a  brass  or  copper  lever  is  fixed  vertically  to 
the  free  end  of  the  roller,  the  other  end  of  this  lever 
being  attached  to  the  horizontal  lever  of  the  self- 
feed  valve.  Usually  a  number  of  holes  are  drilled 
through  the  vertical  lever  at  the  end  which  is 
attached  to  the  self-feed  valve  lever.  These  holes 
are  for  the  purpose  of  allowing  the  taper  to  regulate 
the  height  to  which  the  size  will  rise  in  the  "sow" 
box  before  the  supply  is  cut  off  by  the  combined 
action  of  the  float  roller  and  the  self-feed  valve. 
The  attachment  of  the  float  roller  lever  to  the  self- 
feed  valve  lever  should  be  so  adjusted  as  to  allow 
the  "sow"  box  to  be  worked  as  full  as  possible, 
without  incurring  the  risk  of  boiling  a  portion  of  the 
size  on  to  the  sheet  of  yarn  when  the  requisite 
amount  of  "boil"  is  being  used. 

The  Immersion  Roller. — The  immersion 
roller,  as  its  name  implies,  is  used  for  the  purpose 
of  immersing  the  yarn  in  the  size. 


{ '  Sow  "  Box — Immersion  Roller.  3  2  i 


It  is  generally  believed  that  a  greater  quantity 
of  size  is  put  on  the  yarn  when  this  roller  is  well 
immersed.  This  may  be  so  for  "pure"  sizing  but 
for  "medium"  and  "heavy''  sizing  it  makes  very 
little  difference  whether  the  roller  is  entirely  immersed 
or  not.  The  point  at  which  the  size  is  actually  put 
on  the  yarn  is  where  the  copper  roller  and  the 
finishing  roller  meet.  Therefore,  if  the  size  be  kept 
at  a  sufficiently  high  level  in  the  "sow"  box  to  ensure 
that  the  copper  roller  is  entirely  covered  with  size 
from  the  point  where  it  leaves  the  size,  to  the  point 
of  contact  with  the  finishing  roller,  it  is  practically 
immaterial  where  the  immersion  roller  is  placed  so 
long  as  it  gives  a  level  sheet  free  from  "half  beers." 

The  reason  it  is  advisable  to  lower  the  immersion 
roller  until  the  yarn  is  immersed  in  the  size,  in  the 
case  of  "pure"  sizing,  is  owing  to  the  size  being 
much  thinner,  and  less  viscid,  than  that  used  in 
"medium"  or  "heavy"  sizing.  In  consequence  of 
this  it  does  not  adhere  to  the  copper  roller  the  same, 
but  runs  quickly  off  leaving  places  uncoated  with 
size.  This  would  cause  soft  places  on  the  weavers' 
beam  ;  a  most  objectionable  condition. 

Many  forms  of  skeleton  immersion  rollers  have 

been  placed  on  the  market  at  one  time  or  another. 

It  is  claimed  for  them  that  they  enable  the  yarn  to 

be  immersed  on  both  sides  (if  a  cylindrical  thread 

can  be  said  to  have  sides)!    So  far  as  the  authors 

can  see  these  rollers  possess  no  advantage  over  the 
u 


322       The  Chemistry  and  Practice  of  Sizing. 


old  style  of  roller.  They  do  not  enable  the  size  to 
enter  the  yarn  with  greater  ease  or  uniformity,  and 
they  are  far  more  likely  to  do  harm  than  good  in 
other  ways. 

The  immersion  roller  should  be  set  about  one- 
eighth  of  an  inch  away  from  the  copper  roller,  and 
parallel  with  it  when  they  are  wound  down  to  a 
position  where  their  centres  are  opposite  each  other. 

The  Copper  Roller. — The  copper  roller  is  the 
most  important  roller  about  the  tape  frame  and  no 
machine  can  turn  out  satisfactory  work  with  an 
imperfect  one.  This  roller  consists  of  a  copper 
shell  fitted  to  a  good  strong  shaft  running  through 
the  middle.  The  copper  shell  should  be  from 
three-eights  to  half-an-inch  in  thickness  when  new. 
Wide  rollers  are  subject  to  a  certain  amount  of 
deflection  from  a  true  circle  when  heated,  owing  to 
the  difference  in  the  rate  of  expansion  between  the 
copper  shell  and  the  wrought-iron  shaft  upon  which 
it  revolves  as  a  centre.  This  tendency  to  buckle  is 
more  pronounced  as  the  width  of  the  tape  frame 
increases,  or  the  thickness  of  the  copper  roller  shell 
decreases.  Attempts  are  made  to  remedy  this 
defect  by  having  one  or  more  mid-feathers  turned 
up  to  fit  inside  the  copper  roller.  A  much  better 
plan  is  to  have  an  expansion  joint  fitted  on  the  shaft. 

The  copper  roller  requires  careful  treatment 
and  too  much  care  cannot  be  exercised  by  the 
"taper"  when  cutting  "lappers"  off.     Unless  care 


' '  Sow  "  ifor —  Copper  and  Finishing  Rollers.  323 

be  exercised  the  surface  of  the  roller,  especially  at 
the  sides,  will  soon  be  injured  by  the  point  of  the 
knife  blade  making-  deep  scratches  on  it.  These 
scratches  have  a  tendency  to  nip  the  yarn  as  it  passes 
over  them,  and  in  this  way  more  "lappers"  are 
formed  than  would  otherwise  be  the  case.  By  care- 
ful usage,  and  by  the  periodical  application  of  fine 
emery  cloth  to  the  surface  of  the  copper  roller,  it  is 
possible  to  make  this  roller  work  for  years,  and  at 
the  same  time  to  reduce  " lappers ;'  to  a  minimum 
without  any  necessity  for  having  its  surface  turned 
true  in  a  lathe. 

The  Finishing  Roller. — The  finishing-  roller 
is  a  heavy  cast-iron  shell  fitted  with  wrought-iron 
ends.  It  generally  weighs  from  six  to  seven  pounds 
per  inch  of  length.  A  heavy  roller  is  essential  to 
obtain  a  good  finish,  particularly  in  heavy  sizing. 
Before  being  put  into  use  the  finishing  roller  should 
be  painted,  or  coated  with  oil,  in  order  to  minimise 
corrosion.  It  should  then  be  "lapped,"  first  with  a 
fent,  and  afterwards  with  flannels  of  some  descrip- 
tion. Over  the  flannels  a  cotton  cloth  fent  should  be 
"lapped."  The  object  of  the  flannels  and  the  fent  is 
to  provide  a  level  yielding  surface  to  the  roller,  thus 
enabling  it  to  squeeze  the  superfluous  size  from  the 
yarn  as  it  passes  between  the  copper  roller  and  the 
finishing  roller,  without  injuring  it. 

There  is  a  diversity  of  opinion  as  to  the  best 
kind  of  flannels  to  use  for  the  finishing  roller.  Some 


324       The  Chemistry  and  Practice  of  Sizing. 

prefer  them  made  from  wool,  both  warp  and  weft, 
whilst  others  prefer  a  union  containing  either  a 
cotton  or  a  linen  wTarp,  with  woollen  weft.  For 
economy  and  general  use  the  authors  prefer  a 
linen  warp  union  for  the  bottom  flannel,  and 
a  cotton  warp  union  for  the  other  two.  Each 
flannel  should  be  four  yards  long  when  supplied 
to  the  taper. 

The  objection  to  all-wool  flannels  for  heavy 
sizing  is  that  they  are  apt  to  slip  when  a  new  flannel 
is  put  on.  In  some  cases  the  slipping  occurs  to  such 
an  extent  that  the  flannels  will  continue  to  revolve 
when  the  finishing  roller  is  stopped.  Cotton  unions 
are  not  subject  to  this  fault,  and  they  undoubtedly 
last  longer  than  those  which  are  all  wool.  The 
bottom  flannel  should  be  the  strongest  and  for  this 
reason  a  linen  union  is  preferred. 

Some  of  the  ingredients  used  in  sizing  have  a 
tendency  to  corrode  the  outer  surface  of  the  finishing 
roller.  This  corrosion  does  not  occur  evenly,  and 
in  consequence  it  becomes  necessary  to  "turn  up" 
the  roller  in  a  lathe  periodically,  in  order  to  preserve 
a  true  circular  surface.  This  " turning  up"  reduces 
the  roller  very  considerably  in  weight  each  time  the 
operation  is  carried  out.  This  loss  in  weight  must 
be  regained,  and  it  is  the  practice  to  attach  weights 
to  the  ends  of  the  roller.  This  is  not  the  best  way 
of  overcoming  the  difficulty,  A  better  way  is  to 
remove  the  end  of  the  roller  and  fill  the  hollow 


"Sow"  Box — Finishing  Roller. 


3^5 


shell  with  iron  borings.  In  this  way  100  pounds 
can  often  be  added  to  the  weight  of  the  roller  and 
the  distribution  of  the  added  weight  is  much  more 
uniform  than  would  be  the  case  if  weights  were 
suspended,  or  attached  to  one  or  both  ends  of 
the  finishing  roller. 

The  practice  of  allowing  the  finishing  roller  to 
run  as  long  as  possible  before  stripping  is  false 
economy.  Nothing  looks  more  unworkmanlike,  or 
produces  worse  work,  than  the  presence  of  patches 
of  fents  of  various  widths  and  thicknesses  on  this 
roller.  In  order  to  secure  a  good  level  foundation 
the  finishing  roller  ought  to  be  stripped  three  or 
four  times  a  year.  This  minimises  the  tendency  of 
the  iron  rust  which  forms  on  the  roller  corroding 
more  than  the  bottom  flannel. 

If  finishing  rollers  were  made  with  a  thin  brass 
or  copper  sleeve  over  the  iron  shell  it  is  probable 
that  a  better  average  finish  would  be  obtained,  and 
less  damage  would  be  done  to  the  flannel  through 
corrosion. 

Great  care  should  be  exercised  in  lowering  the 
finishing  roller  on  to  the  copper  roller,  as  the  shaft 
in  the  latter  can  be  easily  strained  if  the  finishing 
roller  is  dropped  abruptly  on  account  of  its  heavy 
weight. 

Some  "sow"  boxes  are  constructed  with  two 
copper  and  two  finishing  rollers.  In  the  opinion 
of  the  authors  no  good  purpose  is  served  by  this 


326      The  Chemistry  and  Practice  of  Sizing. 

device,  because  sufficient  size  can  be  put  on  the 
yarn  for  any  class  of  sizing  and  as  good  a  finish 
can  be  obtained  with  one  copper  roller  and  one 
finishing"  roller  as  with  two  of  each. 

The  Mid-Featiier. — The  mid -feather  is  a 
wooden  partition  dividing  the  "sow1'  box  into  two 
compartments.  The  partition  should  be  arranged 
so  that  there  may  be  a  free  flow  of  size  from  one 
part  of  the  box  to  the  other.  This  may  be  done 
either  by  cutting  a  number  of  holes  in  the  lower 
portion  of  the  mid-feather,  or  by  raising  the  mid- 
feather  by  means  of  two  feet,  one  of  which  should 
be  fixed  at  each  end  of  it.  These  feet  should  stand 
about  three  inches  in  height,  so  that  there  is  a 
space  of  three  inches  between  the  mid-feather 
and  the  bottom  of  the  "sow"  box  for  the  size 
to  flow  through. 

The  addition  of  a  mid-feather  may  be  an 
improvement  in  "pure"  sizing  where  a  pan  is  not 
used  for  boiling  the  size  previous  to  its  entering  the 
box,  but  if  a  boiling  pan  is  used  the  advantages  to 
be  derived  from  a  mid-feather  are  more  imaginary 
than  real, 

The  Falling  Roller. — The  falling  roller  rests 
on  the  sheet  of  yarn  between  two  guide  rollers, 
whose  centres  revolve  in  brackets  fixed  on  the 
"sow"  box  sides.  The  whole  arrangement  is 
placed  between  the  back-beams  and  the  immersion 
roller.     Each  end  of  the  falling  roller  works  in  a 


The  Drying  Cylinders. 


327 


perpendicular  bracket  having  a  long  slot  in  it.  Any 
slackness  of  the  yarn,  caused  by  the  back-beams 
running  irregularly,  or  produced  when  the  machine 
itself  is  stopped,  can  thus  be  corrected  by  the 
weight  of  the  roller  as  it  descends  in  the  slot. 

The  other  fittings  of  the  "sow"  box  are  not 
matters  of  great  importance,  and  they  do  not 
require  detailed  description.  It  is  perhaps  well 
to  state  that  it  is  better  to  have  a  copper  lid  for 
the  "  sow"  box  rather  than  a  wrooden  one,  and 
also  that  it  is  advisable  to  have  a  large  tap  for 
the  purpose  of  drawing  off  the  contents. 

THE  DRYING  CYLINDERS. 
It  is  usual  to  have  two  drying  cylinders  in  a 
tape-frame.      The  diameters  of  the  cylinders  in 
common  use  are  6  feet  and  4  feet ;   7  feet  and 
4  feet ;  and  occasionally  7  feet  and  5  feet. 


WIDTH  OF  CYLINDERS. 


Width  of 
Machine. 

Width  on  face  of 
Tin  Cylinder. 

9/8'S 
6/4'S 
7/4'S 
8/4'S 
9/4'S 

10/4  S 

60  inches. 
66  „ 

72  » 
78  „ 
84  „ 
9° 

It  is  not  necessary  to  go  into  details  regarding 
the  construction  of  the  drying  cylinders  except  to 


The  Drying  Cylinders. 


329 


point  out  the  desirability  of  having  double-acting 
buckets  in  them.  By  this  arrangement  the  con- 
densed water  can  be  removed  whichever  way  the 
cylinders  are  put  in,  or  whichever  way  they  are 
rotated.  These  buckets  will  also  prove  useful  if 
it  be  desired,  when  sizing  coloured  bordered  goods, 
to  run  the  coloured  yarn  next  to  the  surface  of  the 
big  cylinder  instead  of  on  the  top  of  the  grey  yarn. 
In  the  former  arrangement  the  cylinder  would 
revolve  in  a  direction  opposite  to  that  in  which  it 
would  revolve  in  the  latter,  as  shown  in  the  diagram 
under  coloured  tapeing. 

In  order  to  reduce  the  friction  of  the  cylinder 
trunnions  to  a  minimum,  Messrs.  Wm.  Dickinson  & 
Sons,  Machinists,  Blackburn,  have  devised  a  ball- 
bearing arrangement.  An  illustration  of  this  is  given 
on  page  328.  It  consists  of  a  stand  A,  which  is 
bolted  to  the  top  of  the  frame  sides.  This  stand  is 
machined  inside  so  that  the  turned  steel  ring  B 
fits  easily  into  it.  This  ring  is  adjustable  from 
behind  by  means  of  the  three  set  screws  C  and 
encases  the  steel  balls  D,  An  adjustable  outer 
collar  E  helps  to  keep  the  balls  in  their  proper 
position,  thus  giving  correct  guidance  to  the 
trunnions  without  undue  pressure  on  the  steel  balls. 
The  insertion  of  the  balls  is  easily  accomplished  by 
setting  the  collar  E  at  the  required  distance  from  B, 
to  allow  the  balls  to  be  dropped  through  F.  When 
a  sufficient  number  of  balls  have  been  inserted  the 


330      The  Chemistry  and  Practice  of  Sizing. 

collar  E  is  pushed  inwards  into  easy  contact  with 
the  balls  and  fixed  by  means  of  the  set-screws. 

The  "taper"  should  see  that  the  friction  bowls 
upon  which  the  cylinder  trunnions  rest  are  kept  in 
efficient  working  order.  If  yarn  and  dirt  be  allowed 
to  get  entangled  with  them,  and  if  oiling  and  cleaning 
be  neglected,  they  will  either  revolve  irregularly 
or  cease  to  revolve  at  all.  This  must  inevitably 
increase  the  power  required  to  turn  the  cylinders 
and,  at  the  same  time,  increase  the  tension  on  the 
yarn  in  a  corresponding  ratio.  The  consequence 
would  be  that  a  large  amount  of  the  natural  elasticity 
of  the  yarn  would  be  taken  out  at  this  point 
instead  of  being  retained  for  the  process  of  weaving. 
Unnecessary  tension  may  be  caused  also  by  too 
tightly  screwing  the  glands  of  the  stuffing  boxes. 

Steam  Traps. — Each  cylinder  should  be  coupled 
to  a  separate  steam  trap,  fitted  with  a  small  tap,  in 
order  to  allow  the  cold  air  to  escape  when  steam  is 
admitted. 

Steam  traps  are  constructed  in  a  variety  of  ways. 
In  some  forms  the  lid  of  the  trap  can  be  taken  off, 
and  the  ball,  or  valve,  adjusted  whilst  the  machine 
is  working.  Traps  constructed  in  this  way  require 
the  beck  or  cistern  into  which  they  discharge  the 
condensed  water  to  be  placed  on  a  lower  level  than 
the  trap. 

It  is  customary  in  some  districts  to  have  a 
small  force  pump,  driven  from  the  side  shaft,  for  the 


The  Headstock. 


33i 


purpose  of  pumping  the  water  from  the  steam  trap 
to  any  desired  level.  In  the  majority  of  cases  the 
pump  could  be  dispensed  with  if  a  suitable  steam 
trap  were  used.  The  trap  should  be  of  such  a  form 
that  the  pressure  of  the  steam  is  exerted  on  the 
water  in  the  trap.  This  would  force  the  water  from 
the  trap  and  a  lift  of  two  feet  per  pound  of  steam 
pressure  could  be  obtained. 

THE  HEADSTOCK. 

The  headstock  consists  of  a  variety  of  motions, 
the  most  important  of  which  will  be  briefly  described. 

The  Driving  Motion. — The  driving  arrange- 
ment may  be  carried  out  by  means  of  cone  drums, 
change  wheel  driving,  or  by  a  combination  of  both. 

Cone  Drum  Driving. — Cone  drum  driving  is 
undoubtedly  the  best  arrangement  in  many  ways. 
It  enables  the  taper  to  make  slight  but  important 
alterations  in  the  speed  at  which  the  tape  frame  is 
running,  and  the  machine  can  be  started  with  less 
risk  of  a  jerk.  At  the  same  time  cone  drum  driving 
is  not  an  ideal  mechanical  motion,  as  each  portion  of 
the  drum  runs  at  a  different  speed  from  the  rest 
throughout  the  whole  of  its  length.  This  accounts 
for  the  trouble  experienced  by  many  " tapers"  of 
having  a  cone  drum  strap  continually  slipping.  This 
is  especially  the  case  when  the  weaver's  beam  is 
nearly  full,  or  if  extra  "press"  is  being  used. 


332        The  Chemistry  and  Practice  of  Sizing. 

It  appears  to  the  authors  that  a  considerable 
amount  of  this  troublesome  defect  in  cone  drum 
driving  might  be  avoided  if  "  slashing"  machine 
makers  would  make  the  drums  as  long  as  possible, 
and  thus  reduce  the  gradient  of  the  tapered  portion. 
If  this  were  done  a  more  uniform  speed  of  the  space 
covered  by  the  cone  drum  strap  would  be  attained. 
The  diameter  of  the  drums  might  be  considerably 
increased  in  many  cases.  This  would  increase 
the  linear  velocity  of  the  cone  drum  strap,  with  a 
proportional  decrease  of  the  "pull"  required  to  be 
exerted  by  it.  The  speed  of  the  driving  cone  drum 
might  be  increased  also,  with  a  corresponding 
decrease  in  the  number  of  teeth. in  the  small  pinion 
which  drives  the  draw  roller  wheel.  This  would 
further  reduce  the  tension  on  the  cone  drum  straps, 
and  they  would  still  be  transmitting  the  same  amount 
of  work,  but  at  a  greater  velocity. 

One  of  the  simplest  and  most  effective  methods 
of  remedying  a  slipping  strap  (where  a  single  one  is 
used)  is  to  take  the  strap  forks  off,  and  replace  them 
with  forks  to  hold  two  or  three  narrow  straps,  in 
place  of  the  original  wide  one.  Two  straps,  each 
two  inches  in  width,  will  give  a  far  more  satisfactory 
drive  than  a  single  four-inch  strap.  Slipping  of  the 
strap  can  also  be  prevented  by  having  two  straps 
running  one  on  the  top  of  the  other,  the  top  strap 
being  narrower  than  the  under  one.  These  straps 
do  not  retain  the  same  relative  position  to  one 


334      The  Chemistry  and  Practice  of  Sizing. 

another  when  running  owing  to  the  different  speeds 
at  which  they  travel. 

Cone  Drum  and  Change  Wheel  Driving. —  In 
this  form  of  driving  the  length  of  the  drums  may  be 
considerably  reduced.  With  this  arrangement  small 
variations  in  speed  could  be  made  by  altering  the 
position  of  the  cone  drum  straps,  but  greater 
variations  would  require  an  alteration  of  the 
"  change  "  pinion. 

Change  Wheel  Driving. — An  illustration  of 
change  wheel  driving  will  be  found  on  page  333. 
A  is  the  change  wheel  pinion  whilst  B  is  an  adjustable 
carrier  wheel  which  transmits  the  motion  of  A  to 
the  draw  roller  wheel. 

Slow  Motion. — An  auxiliary  to  the  driving 
motion  is  the  slow  motion,  by  means  of  which  the 
frame  can  be  run  at  a  very  low  speed.  This 
arrangement  is  necessary  in  order  to  avoid  producing 
stiff  places  on  the  yarn.  The  stiff  places  are  caused 
by  the  heat  of  the  copper  roller  baking  the  size  on 
the  yarn  when  the  frame  is  stopped  for  any  length 
of  time. 

The  slow  motion  should  be  arranged  to  gear 
with  the  driven  cone  drum  as  shown  on  page  335, 
otherwise  it  is  useless  when  the  cone  drum  strap 
slips  or  breaks. 

The  arrangement  for  converting  the  driven  into 
the  d?Hving  drum,  when  the  slow  motion  is  being 
used,  is  as  follows  : — 


336       The  Chemistry  and  Practice  of  Sizing. 


The  fast  pulley,  shown  with  a  set-screw  in  it,  is 
fastened  to  the  driving  cone  drum  shaft.  The 
lengthened  boss,  B,  of  the  narrow  slow  motion 
pulley,  A,  carries  a  bevel  wheel  and  this  drives 
the  short  side  shaft  C.  Shaft  C,  by  suitably 
proportioned  worm  and  wheel  gear,  E.F.,  and  click 
motion,  G,  engages  with  the  ratchet  wheel  on  the 
shaft  to  which  the  driven  cone,  Dn,  is  fixed,  as  soon 
as  the  speed  of  the  latter  is  on  the  point  of  falling 
below  that  which  the  slow  motion  is  calculated  to  give. 

The  change  of  speed  is  gradual  and  automatic 
and  is  never  allowed  to  fall  below  the  rate  at  which 
the  slow  motion  is  intended  to  run. 

The  arrangement  of  the  three  pulleys  on  the 
driving  shaft  allows,  by  the  continued  one  way 
movement  of  the  "setting"  on  levers,  the  starting  of 
the  machine,  first  to  slow,  and  then  to  full  speed. 
This  is  preferable  to  the  old  system  where  the  loose 
pulley  occupied  the  middle  position. 

The  Friction  Motion. — This  motion  is  for 
the  purpose  of  winding  the  yarn  which  is  delivered 
from  the  draw  roller  at  a  uniform  rate  on  to  the 
weaver's  beam.  This  beam  is  constantly  increasing 
in  circumference  and  it  thus  requires  to  make  a 
correspondingly  decreased  number  of  revolutions 
to  wind  on  a  given  length  of  yarn. 

The  " winding  on"  of  the  yarn  ought  to  be  the 
sole  duty  of  the  friction  motion.  It  should  be 
adjusted  so  as  to  turn  the  bearri  round  without  setting 


The  Friction  Motion. 


337 


up  any  unnecessary  tension  on  the  yarn  between  the 
point  where  it  is  delivered  from  the  draw  roller  to 
the  point  where  it  begins  to  wind  on  the  weavers 
beam.  The  authors  know  of  cases  where  it  is  the 
practice  to  produce  a  hard  weaver's  beam  by 
increasing  the  amount  of  tension  on  the  yarn.  This 
method  cannot  be  too  strongly  condemned.  The 
proper  way  to  increase  the  hardness  of  a  beam  is  to 
increase  the  weight  on  the  press  lever.  The  tension 
on  the  yarn  should  always  be  reduced  to  the  lowest 
workable  amount  when  winding  it  on  the  weaver's 
beam,  thus  retaining  as  much  of  its  elasticity  as 
possible  for  the  process  of  weaving.  This  matter 
has  been  mentioned  previously  when  discussing  the 
drying  cylinders. 

It  is  advisable  to  pull  the  friction  motion  to 
pieces  periodically.  The  plates  and  flannels  should 
then  be  examined  and  any  substances  such  as  rust, 
dried  oil,  or  dirt,  should  be  carefully  removed.  This 
will  prevent  irregular  working. 

A  modern  friction  motion  will  be  found  on  page 
338.  The  anti-friction  bowls,  A,  carried  by  the 
lever,  B,  press  upon  the  friction  plates.  Lever  B 
is  fulcrumed  upon  the  swivel  C,  so  as  to  allow  the 
bowls  to  follow  any  deflection  or  variation  in  the 
plane  of  rotation  of  the  friction  plates.  The  upper 
end  of  lever  B  is  connected  by  the  link  D  to  the 
bell  crank  lever  E,  the  longer  arm  of  which  carries 

one  or  more  weights  F.       These   weights  are 

v 


The  Friction  Motion. 


The  Friction  Motion. 


339 


secured  by  thumbscrews,  so  that  they  can  be 
easily  moved  as  more  or  less  tension  is  required. 

When  changing  the  weaver's  beam  the  lever 
carrying  the  weights  is  turned  up,  This  removes 
the  friction  from  the  plates  and  enables  the  "  taper  " 
to  move  the  mandril  shaft  with  ease, 

It  may  be  advisable  to  point  out  that  the 
alterations  in  speed  of  the  weavers  beam,  necessarily 
involved  by  the  circumference  of  the  beam  increas- 
ing with  each  successive  layer  of  yarn,  are  governed 
entirely  by  the  friction  motion.  The  usual  explana- 
tion given  in  text  books,  "'that  these  alterations  are 
clue  to  altering  the  position  of  the  cone  drum  strap," 
is  wrong.  In  all  modern  machines  the  movement 
of  the  strap  along  the  cone  drums  increases  or 
decreases  the  speed  of  the  machine  as  a  whole. 
The  gradual  decrease  in  the  revolutions  of  the 
weavers  beam  is  due  to  a  corresponding  increase  in 
the  amount  of  slipping  which  takes  place  between 
the  plates  and  flannels  of  the  friction  motion. 

Another  erroneous  idea  is,  that  after  fixing  the 
weight  on  the  friction  lever  to  obtain  the  desired 
tension  for  the  first  beam  of  a  "set,"  no  further 
alterations  are  required  until  the  "set"  is  finished. 
In  good  "tapeing"  practice  the  weight  on  the  lever 
should  be  reduced  to  a  minimum  at  the  commence- 
ment of  a  beam,  and  it  should  be  increased  as  the 
beam  gets  larger.  This  is  essential  to  overcome  the 
extra  power  required  to  turn  the  beam  as  it  increases 


34-0       The  Chemistry  and  Practice  of  Sizing. 

in  weight.  The  leverage  exerted  on  the  beam  by 
the  press  also  increases  with  the  size  of  the  beam. 
If  the  weight  be  fixed  in  such  a  position  as  to  turn 
the  beam  when  full  with  plenty  of  "press"  on,  the 
tension  at  the  beginning  with  the  weight  in  the 
same  position  w7ould  be  sufficient  to  break  some  of 
the  "ends."  The  elasticity  of  the  unbroken  ''ends" 
would  also  be  reduced  to  such  an  extent  as  to  make 
an  appreciable  difference  in  the  weaving. 

The  Draw  Roller. — The  draw  roller  is  a 
"built  up"  wooden  roller  having  a  wrought-iron 
shaft  in  the  centre  upon  which  it  revolves.  Two 
heavy  iron  rollers,  known  as  the  "nip''  rollers,  rest 
on  this  roller.  The  three  rollers  are  used  for  the 
purpose  of  pulling  the  yarn  from  the  cylinders  and 
delivering  it  to  the  weavers  beam.  The  draw  roller 
derives  its  motion,  by  means  of  a  spur  wheel,  from  the 
small  pinion  on  the  end  of  the  driven  cone  drum  shaft. 
It  is  also  geared  with  the  copper  roller  by  means  of 
two  pairs  of  mitre  wheels  on  the  side  shaft.  The 
object  of  the  side  shaft  is  to  relieve  the  tension  on 
the  yarn  by  having  it  delivered  to  the  cylinders 
positively,  and  taken  from  them  in  the  same  way. 
The  yarn  is  thus  relieved  of  considerable  tension  in 
comparison  to  the  amount  to  which  it  was  subjected 
previous  to  the  introduction  of  the  side  shaft.  It 
is  still  possible,  however,  even  with  the  above 
arrangement,  to  subject  the  yarn  to  undue  tension 
if  the  circumferences  of  the  draw  roller  and  of  the 


The  Draw  Roller. 


34i 


copper  roller  are  not  kept  in  the  right  ratio.  The 
circumference  of  the  copper  roller  is  constant,  but 
the  draw  roller  is  "lapped"  with  several  rounds  of 
flannel  in  order  to  prevent  the  yarn  being  injured  by 
the  nip  rollers  which  revolve  on  the  top  of  it.  In 
addition  to  the  flannel,  cotton  fents  are  wound  round 
the  roller,  and  it  is  thus  possible  to  stretch  the  yarn 
to  a  considerable  extent  if  too  many  be  used. 

Where  tapers  are  on  piece-work  there  is  a 
desire  to  get  through  the  work  quickly,  and  this 
can  be  managed  by  putting  extra  fents  on  the  draw 
roller,  the  effect  of  which  is  to  tighten  the  yarn 
round  the  drying  cylinders.  This  makes  it  dry 
more  quickly  owing  to  its  being  brought  into  closer 
contact  with  the  hot  cylinders,  thus  allowing  the 
frame  to  be  run  at  an  increased  speed.  This  speed 
however,  is  obtained  at  the  expense  of  the  elasticity 
of  the  yarn  owing  to  its  being  kept  too  tight  between 
the  copper  roller  and  the  draw  rollers. 

Any  extra  tension  can  be  readily  detected  by  an 
experienced  eye  if  the  amount  of  deflection  of  the 
sheet  of  yarn  from  a  straight  line,  as  it  travels  from 
the  copper  roller  to  the  top  of  the  big  cylinder,  be 
noted.  If  the  yarn  does  not  sag  between  these 
points  it  is  direct  evidence  that  it  is  too  tight. 

Sharp  practice  of  this  description  should  be 
stopped  at  once,  as  the  natural  elasticity  of  the  yarn 
ought  to  be  retained  as  far  as  possible  through  all 
the  preparatory  processes. 


342      The  Chemistry  and  Practice  of  Sizing. 

The  Marking  or  Measuring  Motion. — This 
arrangement  is  used  for  the  purpose  of  marking  off 
the  yarn  to  the  required  length.  There  are  a  variety 
of  motions  for  attaining  this  object.  Some  tape 
frames  are  fitted  with  one  marker  only.  Where 
there  are  a  number  of  marks  in  a  piece  of  cloth  the 
weaver  is  expected  to  count  them  as  they  "weave  in," 
and  finish  the  piece  at  the  right  one.  The  counting 
can  be  avoided  by  having  two  markers,  commonly 
known  as  "dhootie  marking  motion."  A  motion  of 
this  description  is  shown  on  page  343. 

A  is  what  is  known  as  the  bell  wheel  shaft. 
It  derives  its  motion  from  a  train  of  wheels 
actuated  by  the  measuring  roller.  The  dhootie 
marker  G  is  driven  from  the  bell  wheel  shaft  by 
means  of  a  pair  of  bevel  wheels.  The  cut  marker 
F  is  also  driven  by  it  through  the  wheels  E,  D,  C, 
and  the  cross  shaft  B. 

The  bell  wheel  shaft  A  can  be  controlled  by  a  small 
wheel  at  the  front  of  the  headstock.  This  enables 
the  taper  to  set  the  marking  cams  at  the  commence- 
ment of  a  weaver's  beam  to  the  desired  position. 

The  ratio  of  the  number  of  "marks"  made  by 
the  dhootie  and  "cut"  markers  depends  on  the 
number  of  the  teeth  in  the  wheel  C  and  E. 
The  wheel  D  is  simply  a  carrier  used  for 
transmitting  the  motion  of  C  to  E. 

In  weaving  dhooties  it  is  of  the  utmost 
importance  that  the  headings  be  inserted  exactly  at 


Dhootie  Marking  Motion. 
Wm,  Dickinson  &  Sons,  Blackburn. 


344       The  Chemistry  and  Practice  of  Sizing. 

each  side  of  the  mark.  This  is  to  ensure  that  the 
scarves  shall  be  of  uniform  length,  as  buyers  object 
to  varying  lengths.  These  objectionable  variations 
are  due  to  the  weaver  allowing  the  ''mark"  to 
"weave  in"  before  inserting  the  "headings,"  or 
"  middling"  as  it  is  termed. 

In  order  to  reduce  the  number  of  "marks" 
" woven  in"  some  machines  are  fitted  with  three 
markers.  Two  of  these  are  on  the  dhootie  marker 
shaft,  and  one  of  them  is  usually  set  so  as  to  make  a 
mark  a  few  inches  before  the  other,  and  usually  of  a 
different  colour.  The  object  of  this  arrangement  is 
to  warn  the  weaver  of  the  approach  of  the  "mark" 
requiring  a  "middling,"  when  the  first,  or  pilot 
mark,  is  seen  "weaving  in." 

A  three  ' 4 mark"  motion  can  be  used  also  for 
running  alternate  marks  of  unequal  lengths.  If 
it  be  required  to  make  a  mark  in  every  four  yards, 
followed  by  one  in  every  three  yards,  the  measuring 
roller  wheel  and  stud  wheel  are  arranged  to  give 
a  mark  every  seven  yards  on  the  dhootie  marker 
shaft.  The  two  marking  cams  can  then  be  set  in 
such  a  position  that  one  marker  will  drop  three 
yards  in  front  of  the  other. 

The  Pressing  Motion. — A  pressing  motion  of 
some  description  is  fitted  to  all  modern  sizing 
machines.  It  is  used  for  the  purpose  of  closely 
pressing  the  layers  of  yarn  on  the  weavers 
beam.     An   increased   length  of  yarn    can  thus 


Roller  "Presses" 


345 


be  wound  on  each  beam.  This  reduces  the 
number  of  weaver's  beams  produced  from  a  "set" 
of  backbeams,  and  on  this  account  reduces  the 
cost  of  "  drawing  in*"  Another  consideration  is 
that  less  beams  have  to  be  "gaited"  in  the  weaving 
shed. 

There  are  a  variety  of  "  presses "  on  the 
market,  some  of  which  have  one  roller,  whilst 
others  have  two. 

One-Roller  u  Press." — One  of  the  latest  one- 
roller  "  presses  "  is  shown  on  page  348.  In  the 
majority  of  these  "presses"  the  roller  is  a  few  inches 
narrower  than  the  space  between  the  beam  flanges. 
Suitable  mechanism  is  arranged  to  impart  a  travers- 
ing motion  to  the  roller,  first  in  one  direction,  then 
in  the  other.  In  the  illustration  it  will  be  seen  that 
a  single  iron  roller  on  the  expanding  principle  is 
used.  This  is  "set"  within  two  or  three  inches  of 
the  width  required  and  it  gradually  works  itself  out 
until  it  is  in  contact  with  both  beam  flanges, 

Instead  of  the  usual  rack  wheel  and  catch,  a 
friction  motion  as  shown  in  the  illustration  may 
be  used.  This  is  fixed  on  the  square  shaft  at  the 
opposite  end  to  the  weight.  The  amount  of  ''press" 
on  the  beam  can  be  regulated  by  increasing  or 
decreasing  the  pressure  on  the  "friction,"  as  well  as 
by  regulating  the  position  of  the  weight  on  the 
"press"  lever.  The  authors  have  not  seen  anything 
to  equal  this  "friction"  motion  for  producing  a  true 


Two- Roller  "Press!1 


347 


beam  on  a  crooked  beam  barrel.  This  friction 
motion  can  be  applied  either  to  the  one  or  to  the 
two-roller  " press." 

Two-Roller  "Press." — The  two-roller  ''press" 
is  arranged  to  have  each  roller  tending  to  travel 
laterally  in  opposite  directions.  An  illustration  of 
the  front  portion  of  a  headstock  with  a  two-roller 
"  press,"  fitted  to  it  is  shown  on  page  346. 

The  pressing  rollers  A,  B,  are  adjusted  by 
means  of  the  small  screws  seen  beneath  the  friction 
bows  C,  so  that  the  revolution  of  the  beam  will 
cause  one  roller  to  move  to  one  side  of  the  beam 
until  it  comes  into  contact  with  the  inside  of  the 
flange.  The  other  roller  does  the  same  in  the 
opposite  direction  so  that  the  whole  of  the  beam  is 
subjected  to  pressure.  The  required  degree  of 
pressure  can  be  obtained  by  altering  the  position 
of  the  weight  upon  the  lever  D. 

Nearly  every  maker  has  some  special  modifica- 
tion of  the  two-roller  " press,"  but  they  all  have  one 
grave  defect,  and  that  is,  they  have  a  tendency  to 
scrape  the  paint  off  the  beam  flanges.  This  is 
responsible  for  the  majority  of  the  iron-stained 
selvedges  produced  in  the  cotton  trade. 

The  ideal  "press"  roller  has  yet  to  be  produced 
and  an  inventor  who  can  bring  out  one  which  will 
press  uniformly  across  the  beam,  and  produce  a 
true  beam  automatically  without  scratching  the 
paint  off  the  flanges,  will  find  a  ready  sale  for  it. 


Fans —  The  Wraith. 


349 


The  amount  of  " press"  required  for  beams 
varies  with  the  '"sorts."  Beams  requiring  plenty 
of  weight  in  the  weaving  shed  should  have  the 
maximum  amount  of  weight  put  on  the  ''press" 
lever,  in  order  to  prevent  the  sides  sinking  in  when 
nearing  the  bottom  of  the  beam.  Very  heavily 
sized  goods,  especially  when  "taped"  damp,  require 
very  little  pressing. 

Fans. — One  or  more  fans  are  fixed  between  the 
place  where  the  yarn  leaves  the  small  cylinder 
and  the  cone  drums.  These  fans  consist  of  three 
wooden  blades  bolted  on  castings  and  fitted  to  a 
shaft.  This  shaft  is  arranged  to  revolve  at  a  high 
speed.  The  fans  are  used  to  cool  and  further  dry 
the  yarn  after  it  has  left  the  hot  cylinders. 

Wheels,  which  have  a  fair  amount  of  metal  in 
the  rims,  are  usually  fixed  on  the  fan  shafts.  These 
wheels  serve  the  same  purpose  as  the  fly-wheel  in 
an  engine.  The  power  required  to  start  them  tends 
to  prevent  the  machine  beginning  with  a  jerk  when 
the  driving  strap  is  put  on  the  fast  pulley,  and  the 
energy  stored  up  in  them  keeps  the  machine 
running  a  few  yards  after  the  strap  is  taken  off 
the  fast  pulley. 

The  Wraith. — This  is  a  comb  which  is  placed 
in  front  of  and  parallel  with  the  weaver's  beam.  It 
is  fitted  with  iron  teeth,  each  of  which  is  inserted 
between  the  coils  of  a  series  of  spiral  springs.  The 
ends  of  the  springs  are  fastened  to  a  bracket  which 


350       The  Chemistry  and  Practice  of  Sizing. 


also  acts  as  a  nut.  The  two  nuts,  one  of  which  has 
a  right  and  the  other  a  left  hand  thread,  are 
screwed  on  a  rod.  By  turning  the  handle  at  the 
front  of  the  machine  the  "  taper"  can  impart  a 
rotary  motion  to  this  rod.  If  the  handle  be  turned 
in  one  direction  the  spiral  springs  are  stretched 
and  all  the  teeth  of  the  wraith  expand  equally.  If 
the  handle  be  turned  in  the  other  direction  they 
contract.  The  sheet  of  yarn  Maid  in"  between 
the  teeth  can  thus  be  made  wider  or  narrower 
as  required. 

Another  motion  is  fixed  to  the  opposite  side  of 
the  machine  by  means  of  which  the  wraith  can  be 
moved  sideways  without  altering  the  distances 
between  the  teeth.  These  two  motions  enable  the 
"  taper"  to  adjust  the  yarn  to  the  width  between  the 
flanges  of  the  weavers  beam. 

A  small  ratchet  wheel  is  usually  fixed  to  one  end 
of  the  screwed  rod.  Intermittent  motion  can  be 
imparted  to  this  wheel  by  means  of  a  driving  "paul" 
having  a  reciprocating  motion  derived  from  a  cam 
on  the  driven  cone  drum  shaft.  When  the  yarn  on 
the  weaver's  beam  is  within  a  short  distance  of  the 
top  of  the  flange  the  "paul"  is  put  in  gear  with  the 
ratchet  wheel  This  causes  the  wraith  to  contract 
and  the  sheet  of  yarn  gradually  decreases  in  width 
as  each  successive  layer  is  wound  on  the  beam. 
The  sides  of  the  sheet  of  yarn  are  thus  made  to 
slope  inwards.     By  this  means  a  greater  length  can 


The  Wraith — ' '  Crooked  Beams. "  351 


be  put  on  a  beam  without  much  risk  of  the  sides 
beinof  damaged. 

When  the  yarn  is  wound  in  at  the  top  of  a  beam 
as  just  described  it  often  leads  indirectly  to  what 
are  known  in  the  weaving  shed  as  " crooked  beams." 
Instead  of  all  the  " threads"  coming  off  the  beam 
straight  and  parallel  to  each  other  some  of  them 
will  be  crossed  at  regular  intervals  across  the  beam. 
The  beam  will  look  all  right  and  straight  when 
"gaited  up/'  but  the  ends  get  crossed  by  the  time 
the  yarn  has  woven  down  to  the  level  of  the  flange. 
The  crossing  of  the  " threads"  is  caused  by  the 
formation  of  very  fine  grooves  in  the  "sheeting 
rollers,"  which  are  placed  in  front  of  the  wraith. 
Some  of  the  threads  of  yarn  run  in  these  grooves, 
and  when  the  wraith  is  being  contracted  they  stick 
in  the  grooves  whilst  the  others  are  being  pushed 
inward  by  the  teeth  of  the  wraith.  The  ends 
which  stick  in  the  grooves  are  those  which  are 
found  "  crossed"  in  the  weaving  shed.  If  the 
sheeting  rollers,  especially  the  lower  one,  are 
periodically  glazed  on  an  emery  wheel  "  crooked 
beams  "  will  be  reduced  to  a  minimum. 

For  dhootie  borders,  the  teeth  at  each  side  of 
the  wraith  are  made  a  few  inches  longer  than  those 
in  the  middle.  This  is  to  keep  the  coloured  ends 
in  their  places,  and  it  is  an  essential  arrangement  on 
account  of  the  coloured  yarn  being  on  a  higher  level 
than  the  grey  yarn  during  the  operation  of  sizing. 


352      The  Chemistry  and  Practice  of  Sizing. 

The  teeth  of  the  wraith  should  be  examined 
periodically,  in  order  to  ascertain  whether  grooves 
are  being  worn  in  them.  This  condition  should  be 
avoided  as  the  threads  tend  to  run  in  the  grooves. 
The  result  is  that  if  there  is  any  unevenness  in  the 
thread,  or  if  there  is  a  knot  or  lumpy  place,  the  yarn 
generally  breaks,  producing  crooked  ends  and 
causing  extra  work  for  the  weaver.  The  insertion 
of  new  teeth,  especially  at  the  sides  of  the  wraith, 
will  stop  this  trouble. 

The  Lease  Rods. — The  lease  rods  are  hollow 
iron  rods,  pointed  at  each  end.  They  are  fitted 
into  brackets  on  each  side  of  the  headstock.  The 
lease  rods  are  used  for  the  purpose  of  separating  the 
whole  sheet  of  yarn  into  as  many  sheets  as  there 
are  backbeams. 

The  constant  friction  of  the  yarn  on  the 
lease  rods  wears  fine  grooves  in  them.  Should 
these  be  allowed  to  get  too  deep  they  will  cause 
the  yarn  to  break,  on  account  of  the  "ends"  catching 
in  them  when  the  rods  are  inserted.  These 
grooves  can  be  removed  by  glazing  the  rods  on 
an  emery  wheel,  or  by  having  them  turned  up 
in  the  lathe. 

Case-hardened  lease  rods  can  now  be  obtained. 
These  rods,  owing  to  their  being  so  much  harder 
on  the  surface  than  the  ordinary  rods  made  from 
wrought-iron  piping,  reduce  the  tendency  to  groove 
to  a  minimum. 


The  Reducing  or  Equilibrium  Valve.  353 

The  Reducing  or  Equilibrium  Valve. — This 
is  a  valve  placed  between  the  cylinder  steam  feed 
tap  and  the  cylinder,  It  is  used  for  the  purpose  of 
reducing  the  pressure  of  the  steam  in  the  feed  pipe, 
and  maintaining  it  at  a  lower  pressure  in  the  cylinders. 
The  pressure  can  be  varied  by  altering  the  position 
of  a  weight  on  the  valve  lever.  If  this  valve  be  in 
good  working  order  the  pressure  in  the  cylinder  can 
be  kept  practically  constant  when  the  machine  is 
running.  A  valve  which  has  a  tendency  to  stick 
instead  of  working  freely  may  lead  the  " taper"  into 
trouble,  as  the  pressure  in  the  cylinders  will  not  be 
uniform.  This  will  give  rise  to  uneven  drying  of 
the  yarn.  In  such  a  case  the  piston  should  be  taken 
out  of  the  valve  and  washed  with  a  strong  solution 
of  soap  in  hot  water.  By  this  treatment  it  is 
often  possible  to  make  a  "sticking"  valve  work 
satisfactorily. 

Some  machines  have  an  arrangement  fitted  to 
the  "setting  on"  rod  for  lifting  the  reducing  valve 
lever  when  the  machine  is  on  the  slow  motion.  By 
this  means  the  supply  of  steam  to  the  cylinders  is 
stopped.  Without  this  arrangement  steam  would 
be  wasted  by  being  forced  into  the  cylinders  until 
the  pressure  was  sufficient  to  open  the  safety  valve. 
With  this  arrangement  there  is  less  tendency  to 
scorch  the  yarn  round  the  cylinders  when  the 
machine  is  being  run  on  the  slow  motion  for  a 

few  minutes. 

w 


354      The  Chemistry  and  Practice  of  Sizing. 

It  may  be  as  well  to  point  out,  however,  that 
even  when  the  above  arrangement  is  fixed,  and  in 
good  working  order,  the  cylinders  will  be  hot  and 
full  of  steam  when  the  machine  stops.  If  the 
pressure  of  the  steam  in  the  cylinders  falls,  the  heat 
which  is  lost  has  been  transferred,  to  a  great  extent, 
to  the  yarn  round  them.  From  this  it  will  be  seen 
that  cutting  off  the  steam  when  the  machine  stops 
is  only  reducing  very  slightly  the  tendency  of  the 
yarn  to  become  over-dried. 

A  good  4<  taper,"  who  understands  his  work,  will 
shut  off  the  steam  and  reduce  the  temperature  of 
the  cylinders  by  ''running  on"  a  few  yards  before 
he  stops  the  machine,  and  in  this  way  avoid 
over-drying. 

THE  PRACTICE  OF  TAPE  SIZING. 

The  chief  mechanical  motions  of  which  a  tape- 
sizing  machine  is  composed  have  been  described 
and  it  will  now  be  followed  by  a  description  of  the 
process  itself. 

The  "  tape-sizer "  holds  the  most  lucrative 
position  as  a  workman  in  the  weaving  branch  of 
the  cotton  industry.  The  responsibilities  of  the 
position  vary  considerably.  "Tapers"  who  run 
"pure"  sized  goods  bear  the  least  responsibility 
and  have  the  easiest  work.  Those  engaged 
on    heavy    sized    goods,    shirting    dhooties,  or 


The  Practice  of  ' '  Tapeing. "  355 


fancy  coloured  work,  require  much  more  skill 
and  experience.  , 

The  points  of  greatest  importance  in  one  class 
of  "tapeing"  are  of  minor  importance  in  another. 
A  "taper"  who  has  had  experience  only  with  "pure" 
sizing  would  probably  find  himself  in  difficulties  if 
he  were  transferred  to  "heavy"  sizing.  Similarly, 
a  "taper"  whose  experience  is  limited  to  plain 
goods  has  a  number  of  things  to  learn  when  placed 
in  charge  of  a  machine  running  coloured  dhootie 
borders,  which  have  a  fair  percentage  of  size  on  the 
grey  yarn.  Men  who  are  accustomed  to  the  latter 
class  of  work,  and  who  do  it  well,  have  to  exercise 
more  care  and  skill  in  running  one  set  of  beams 
than  is  required  to  run  two  ordinary  "pure"  sized 
"  sets." 

It  would  be  impossible  to  make  a  "taper"  by 
giving  full  and  minute  details  of  the  work,  and 
therefore  much  will  be  left  out  of  this  chapter 
which  might  otherwise  have  been  included  in  it. 
At  the  same  time  the  authors  intend  to  describe  and 
discuss  all  points  of  importance,  with  a  view  to 
imparting  more  definite  and  accurate  practical 
information  on  the  subject  than  has  yet  been 
published.  This  information  cannot  fail  to  be 
advantageous,  not  only  to  the  practical  " taper,"  but 
also  to  the  manufacturer  and  the  mill  manager. 

General  Directions  for  Starting  the  Tape 
Frame. — Assuming  that  the  "taper"  has  finished  a 


356      The  Chemistry  and  Practice  of  Sizing. 

"set"  one  of  his  first  duties  will  be  to  change  the 
wheels,  if  the  next  "set"  requires  to  be  marked  in  a 
different  manner.  After  changing  the  wheels  the 
required  number  of  backbeams  constituting  the  "set" 
should  be  put  in ;  care  being  taken  to  put  them  in  to 
run  the  right  way,  and  to  have  each  succeeding 
beam  narrower  than  the  one  preceding  it,  provided 
there  is  any  difference  in  their  width. 

Having  got  the  beams  in  they  should  be  care- 
fully examined  to  see  if  they  have  the  right  number 
of  "ends,"  with  the  right  counts  of  yarn,  and  the  same 
length  as  entered  in  the  book,  otherwise  the  "set" 
may  be  started  with  a  wrong  backbeam  in. 

The  warpers  number  should  also  be  entered  in 
the  taper  s  book  opposite  to  the  respective  beams,  so 
as  to  enable  him  to  put  the  blame  on  the  right 
shoulders  if  there  should  be  any  bad  work  on  a 
backbeam. 

After  the  beams  have  been  examined  the  weigh- 
ing straps  should  be  put  on  the  two  last  beams  of  the 
"set."  These  straps,  which  are  placed  on  the  boss 
of  the  beam  flange,  are  used  for  the  purpose  of 
preventing  the  backbeams  over-running  themselves 
when  the  machine  stops. 

There  are  two  methods  of  putting  these 
leather  straps  on  the  beam  flanges,  a  right 
way  and  a  wrong  way.  An  illustration  of  the 
right  and  wrong  way  is  shown  in  the  diagram  on 
Page  357. 


Wrong  Method  of  Weighting  the  Backbeams. 


358       The  Chemistry  and  Practice  of  Sizing. 


When  the  strap  is  put  on  the  beam  flange 
correctly  the  friction  of  the  flange  against  the  strap 
tends  to  lift  the  weights  up  and  slacken  the  strap. 
When  it  is  put  on  incorrectly  it  causes  the  strap 
to  tighten,  and  the  amount  of  friction  becomes 
excessive  whilst  the  yarn  is  unduly  stretched.  In 
the  correct  method  of  putting  on  the  strap  the 
friction  is  definite  according  to  the  weight,  whereas 
in  the  incorrect  method  it  is  an  indefinite  and 
unknown  quantity,  although  the  weight  is  the  same 
in  both  cases. 

When  the  beams  have  been  adjusted,  and  the 
ends  in  the  new  "set"  tied  to  the  tail  end  of  the  old 
one,  the  pinion  on  the  driven  cone  drum  shaft  is  put 
into  gear.  The  weavers  beam  and  the  friction 
motion  should  be  also  set  right.  The  steam  tap 
leading  to  the  cylinders  is  then  opened.  This 
forces  the  water  which  has  been  condensed  in 
the  pipes  to  the  cylinders.  The  taps  leading 
to  the  boil  pipes  are  afterwards  opened.  If 
these  taps  were  opened  before  the  tap  leading  to  the 
cylinders  the  water  would  be  driven  into  the  "sow" 
box.  This  would  cause  the  size  to  be  diluted  and  if 
the  tape  frame  were  situated  a  long  distance  from 
the  boiler  there  might  be  sufficient  condensed  water 
in  the  pipes  to  make  an  appreciable  difference  in  the 
strength  of  the  size.  Such  cases  are  not  unknown 
to  the  authors.  An  instance  of  the  effect  of 
condensation  came  under  their  notice  recently.  In 


The  Practice  of  a  Tap  dug."  359 


this  case  the  particular  firm  had  only  just  commenced 
to  tape-size  their  yarns.  The  tape  room  was  a  one- 
storied  building  with  an  iron  roof,  and  it  was  situated 
a  good  distance  from  the  boiler.  They  were  using  an 
experimental  "mixing,"  containing  a  large  percentage 
of  Epsom  salts,  in  order  to  put  on  100  per  cent,  of 
size.  The  first  beam  which  was  run  gave  about 
95  per  cent,  of  size,  the  second  dropped  down 
to  87  per  cent.,  whilst  on  the  third  they  could 
get  only  about  60  per  cent.  On  investigation 
it  was  found  that  an  enormous  quantity  of 
condensed  water  was  getting  into  the  "mixing." 
This  water  came  from  the  pipes,  and  down  the 
trunk  on  the  tape-frame.  The  trouble  was 
stopped  by  fixing  a  steam  trap  to  the  pipes 
as  near  to  the  tape-frame  as  possible,  and  by 
attaching  a  gully  to  the  rim  of  the  trunk  so  as  to 
prevent  the  condensed  water  running  into  the 
"sow"  box. 

After  the  size  has  been  boiled,  the  finishing  roller 
should  be  put  down,  and  then  the  tape  frame  should 
be  run  a  short  distance  on  the  slow  motion,  in  order 
to  allow  the  sheet  of  yarn  to  get  straight.  The 
"lease  bands"  should  then  be  put  in.  These  "bands" 
are  pieces  of  cotton  waste  a  few  inches  longer  than 
the  width  between  the  backbeam  flanges.  They  are 
inserted  between  the  ends  of  each  beam  in  the  "set.'' 

After  putting  in  the  "bands,"  the  teeth  of  a  comb, 
known  as  the  "striking  comb,"  are  inserted  in  the 


360      The  Chemistry  and  Practice  of  Sizing, 

sheet  of  yarn.  The  number  of  teeth  in  the  comb 
depends  upon  the  number  of  teeth  in  the  "wraith," 
and  upon  the  width  of  weavers  beam  it  is  intended  to 
use.  The  place  where  the  comb  is  generally  inserted 
is  behind  the  guide  roller  which  is  nearest  to  the 
immersion  roller.  It  should  be  inserted  in  the  sheet 
of  yarn  about  two  yards  in  advance  of  the  first 
"lease  band." 

The  teeth  of  the  comb  divide  the  sheet  of  yarn 
into  a  number  of  narrow  strips,  with  a  space 
between  each.  If  the  teeth  are  equidistant,  and 
the  sheet  of  yarn  uniform  in  density,  each  strip 
will  contain  approximately  an  equal  number  of 
ends. 

It  is  customary  to  make  a  mark  on  the  middle 
strip,  with  a  finger  previously  smeared  with  black 
oil.  The  position  of  the  middle  strip  is  ascertained 
by  means  of  a  piece  of  yarn,  which  is  tied  round  the 
back  of  the  comb  exactly  midway  between  the  end 
teeth. 

After  pulling  the  comb  out,  the  machine  is  run 
until  these  strips,  or  the  "striking"  as  it  is  generally 
termed,  get  to  the  "wraith."  Whilst  the  "striking" 
is  being  run  from  the  back  to  the  front  of  the  machine 
the  "lease"  rods  are  pulled  out  of  their  brackets  and 
laid  on  the  floor.  The  "wraith"  is  also  turned  oven 
This  is  done  to  prevent  the  knots,  which  have  been 
formed  by  tying  the  ends  of  the  old  and  new  sets 
together,  getting  broken. 


The  Practice  of  ' '  Tapeing, 1 9 


361 


When  the  "striking"  has  reached  the  "  wraith," 
and  the  sheet  of  yarn  has  been  straightened,  the 
"wraith''  is  turned  up  to  its  working  position.  The 
strip  of  yarn,  with  the  black  oil  smear  on  it,  is 
inserted  in  the  space  between  the  middle  tooth  and 
the  one  next  to  it.  Each  consecutive  strip  is  then 
inserted  between  the  teeth,  care  being  taken  not  to 
put  two  strips  in  one  space,  nor  to  leave  a  space 
without  one.    This  operation  is  termed  "laying  in." 

As  it  takes  a  few  minutes  for  the  above  operations 
the  slow  motion  is  allowed  to  work  intermittently  in 
order  to  prevent  the  formation  of  stiff  places  through 
the  size  baking  on  the  yarn.  This  would  happen  if 
the  machine  were  stopped  altogether,  owing  to  the 
heat  of  the  copper  roller. 

It  is  a  practice  with  some  "tapers  "  to  keep  the 
cylinder  steam  tap  open  whilst  "laying  in,"  so  as  to 
be  able  to  get  running  quickly.  This  practice  is  not 
a  good  one,  as  the  yarn  round  the  cylinders  becomes 
scorched  through  excessive  drying.  If  chloride 
of  magnesium  be  an  ingredient  of  the  size,  this 
overheating  may  cause  the  yarn  to  become 
"tendered." 

After  "laying  in"  a  "lease  rod"  is  inserted 
between  each  of  the  "lease  bands"  to  separate 
the  combined  sheet  of  yarn  into  as  many  sheets 
as  there  are  backbeams  in  the  creel.  By  this 
means  all  the  ends  are  separated  from  one  another. 
The  brackets  holding  the  rods  should  be  adjusted 


362      The  Chemistry  and  Practice  of  Sizing. 

so  as  to  allow  each  individual  sheet  to  travel 
along  through  the  u wraith"  apart  from  any  other 
sheet. 

The  back  "lease  rod"  is  usually  much  thicker 
than  any  of  the  others  and  for  " heavy"  sizing  a  rod 
made  from  two-inch  piping  is  not  too  large. 

After  the  rods  have  been  got  in,  the  weaver's 
beam,  upon  which  the  "gaiting  up"  has  been  wound, 
is  pulled  out  and  a  fresh  one  inserted  in  its  place. 
The  marking  motion  is  then  turned  to  the  right 
place,  and  the  finger  of  the  dial  set  at  figure  O. 
The  " wraith"  is  then  adjusted  so  as  to  give  a  sheet 
of  yarn  equal  in  width  to  the  distance  between  the 
beam  flanges.  The  press  rollers  are  afterwards 
lifted  up  to  the  beam.  Steam  is  then  turned  into 
the  cylinders,  the  size  and  boil  taps  are  adjusted,  and 
the  frame  is  run  at  a  low  speed  until  the  cylinders 
get  hot.  During  this  period  the  " taper"  generally 
straightens  any  inequalities  in  the  sheet,  by  lifting 
"ends"  out  of  spaces  in  the  "wraith"  (which  may 
accidently  contain  too  many),  and  dividing  them 
into  the  adjoining  spaces  which  may  contain  too 
few.  This  is  done  to  obtain  a  sheet  of  uniform 
thickness,  by  which  means  the  weaver's  beam  is 
made  the  same  degree  of  hardness  all  the  way 
across. 

This  straightening  up  of  the  sheet  should  always 
be  performed  as  near  the  bottom  of  a  beam  as 
possible,  as  every  end  lifted  over  will  come  up 


The  Practice  of  "  Tap  dug."  363 


crooked  in  the  weaving  shed,  from  the  place  where 
it  is  lifted  over,  to  the  bottom  of  the  beam. 

Too  much  care  cannot  be  exercised  in  oettino-  a 
good  straight  bottom,  free  from  broken  yarn,  for 
every  weaver's  beam.  If  the  machine  be  started  at 
a  high  speed,  and  the  width  of  the  yarn  in  the 
"wraith"  is  either  considerably  narrower  or  broader 
at  one  side,  or  both,  than  the  distance  between  the 
beam  flanges,  "ends"  are  almost  sure  to  be  broken, 
or  a  "soft''  side  formed. 

By  approximately  adjusting  the  width  of  the  yarn 
in  the  u  wraith"  whilst  on  the  slow  motion,  and  then 
running  slowly  for  a  few  yards  until  it  is  accurately 
adjusted,  the  "taper"  can  save  the  weavers  endless 
trouble. 

Having  described  how  a  "set"  is  "gaited  up," 
the  chief  points  requiring  attention  afterwards  will 
be  briefly  dealt  with. 

Insertion  of  "Doffing  Combs." — When  the 
weavers  beam  has  been  filled  with  yarn  a  comb 
should  be  put  in  before  it  is  disconnected  from  the 
tape  frame.  This  comb  is  put  in  to  keep  the  "ends" 
straight  for  the  "  reacher-in "  when  he  is  selecting 
"ends."  It  is  not  an  uncommon  practice  for  tapers 
to  "doff"  a  beam  without  putting  a  comb  into  it. 
The  result  of  this  bad  practice  is  to  produce 
"crossed  ends"  in  the  weaving  shed.  Occasionally 
these  "crossed  ends"  are  put  down  to  the  size 
sticking  the  yarn  together  and  they  are  described  as 


364       The  Chemistry  and  Practice  of  Sizing. 


"  stickers."  It  is  not  a  case  of  the  sized  yarn 
sticking  together  at  all  but  to  the  cause  mentioned, 
"  Crossed  ends"  can  be  produced  if  the  teeth  of 
the  combs  are  not  kept  in  good  order. 

"  Broken  Bottoms." — These  consist  of  a  con- 
siderable number  of  "ends"  which  are  broken  at  the 
point  where  they  are  wound  on  the  weaver's  beam. 
"Broken  bottoms"  occur  mostly  in  heavily  sized 
goods,  or  in  "sorts"  where  the  number  of  "ends'' 
forming  the  beam  are  few.  The  tendency  to  form 
"broken  bottoms"  may  be  avoided  by  attention  to 
the  following  instructions  : — 

(1)  The  steam  to  the  cylinders  should  be  shut 
off  about  fifty  yards  previous  to  getting  to  the  top 
of  a  beam. 

(2)  The  tape  frame  should  be  run  slowly  until 
the  yarn,  which  has  been  on  the  cylinders  during  a 
stoppage,  and  thus  over-dried,  is  wound  on  the 
weaver  s  beam. 

(3)  The  weight  on  the  friction  lever  should  be 
reduced  to  the  lowest  possible  working  amount,  or 
it  should  be  pulled  off  altogether,  during  the  time  the 
previously-mentioned  dry  yarn  is  winding  round  the 
beam.  If  these  instructions  are  carefully  carried 
out  the  "taper"  will  turn  out  better  work,  and, 
at  the  same  time,  enhance  his  reputation  as  a 
workman. 

Over- Dried  Yarn. — Over-dried  yarn  may  be 
rectified  to  a  certain  extent  by  treating  it  with  steam. 


The  Practice  of  "  Tapeing." 


365 


A  steam  pipe,  in  which  a  number  of  small  holes  are 
bored,  is  placed  in  some  position  between  where  the 
yarn  leaves  the  small  cylinder  and  the  back  " lease 
rod."  This  pipe  should  be  fitted  with  a  steam  tap, 
and  the  holes  should  face  in  the  direction  of  the 
yarn.  By  opening  the  steam  tap  live  steam  can 
be  impinged  on  the  yarn.  This  is  allowed  to 
continue  until  that  portion  of  yarn  which  is  over- 
dried  is  wound  on  the  beam. 

"Tapeing"  "Light"  Sized  Yarn, — "Pure,"  or 
''light"  sized  goods,  irmst  be  well  dried  in  the 
"taping,"  especially  at  the  lower  portion  of  the  beam, 
otherwise  they  will  be  liable  to  mildew.  At  the 
same  time  care  must  be  taken  to  avoid  over-drying. 
"Heavy"  sized  yarns  are  not  nearly  so  liable  to 
develop  mildew,  because  they  contain  sufficient 
chloride  of  zinc  to  prevent  this  trouble,  whereas 
pure  or  light  sized  yarns  rarely  contain  chloride  of 
zinc,  or  other  antiseptic.  Mildew  is  a  serious 
matter  in  "  pure "  sized  goods  unless  they  are 
intended  for  bleaching.  In  the  latter  case  it  does 
not  matter  much,  unless  the  mildew  has  attacked 
the  cotton  fibre,  or,  unless  it  has  produced  a  "soft 
beam." 

It  requires  experience  to  be  able  to  say  when  a 
yarn  is  sufficiently  well  dried,  without  fear  of  its 
being  under  or  over-dried.  The  "  feel  "  of  the  yarn 
as  it  passes  between  the  thumb  and  fingers  is  the 
usual  method  of  judging  its  dryness.    The  place 


366      The  Chemistry  and  Practice  of  Sizing. 

where  the  test  should  be  applied  is  between  the  draw 
roller  and  the  weaver's  beam. 

In  "  pure  "  sizing  it  is  advisable  to  have  the  lower 
portion  of  the  immersion  roller  below  the  surface  of 
the  size  in  the  "sow  "  box,  in  order  to  prevent  any 
portion  of  the  yarn  being  unsized  when  the  machine 
is  on  the  slow  motion. 

As  previously  stated,  uniform  work  of  good 
quality  in  "  pure  "  sizing  demands  no  great  amount 
of  skill  from  the  "  taper  "  if  the  yarn  be  sufficiently 
good  in  quality  and  the  size  be  suitable  for  the  "sort  " 
for  which  it  is  intended.  At  the  same  time  the 
difference  between  paying  attention  to  many  of  the 
details  mentioned  in  the  previons  portion  of 
this  chapter,  and  being  careless,  is  sufficient  to 
earn  a  "taper"  a  good  name  as  a  workman  or 
otherwise. 

"  Tapeing  "  "  Medium  "  and  "  Heavy  "  Sized 
Yarns. — In  "medium''  and  "heavy"  sizing  the 
"  taper "  is  expected  not  only  to  produce  a  yarn 
which  shall  weave  well,  but  he  has  to  incorporate 
a  considerable  quantity  of  size  with  it  as  well,  This 
weight  may  vary  from  20  or  30  up  to  200  per  cent. 
It  may  be  desirable  to  have  a  certain  "feel  "  on  the 
cloth  also.  It  is  essential,  therefore,  that  the  weight 
and  "feel"  be  kept  as  uniform  as  possible.  These 
conditions  should  be  taken  into  consideration  when 
making  the  "mixing"  otherwise  it  is  practically  im- 
possible for  the  "  taper  "  to  obtain  them.     If  they  have 


The  Practice  of  "  Tap  dug." 


367 


been  taken  into  consideration, and  a  suitable  "mixing" 
made,  it  is  still  possible  for  a  careless  "taper" 
to  produce  beams  which,  when  woven,  give 
a  wide  range  of  weights  and  a  great  variety  of 
"feels"  instead  of  the  desired  uniformity. 

In  order  to  attain  uniformity  in  sizing  it 
is  essential  that  the  following  conditions  should  be 
observed  : — 

(1)  Each  size  "mixing"  should  be  uniform  in 
strength  and  in  the  percentages  of  the  ingredients 
of  which  it  is  composed. 

(2)  The  ingredients  should  be  treated  in  the 
same  manner  for  every  il  mixing"  for  the  same 
"sorts." 

(3)  The  size  should  be  fed  into  the  "sow"  box 
uniformly. 

(4)  The  size  should  be  well  and  evenly  boiled. 

(5)  The  speed  at  which  the  machine  is  run  should 
be  regulated  so  as  to  dry  the  yarn  uniformly. 

(6)  The  "taper"  should  have  sufficient  intelli- 
gence and  experience  to  enable  him  to  judge,  by  the 
"feel"  of  the  yarn,  whether  these  five  conditions  are 
being  complied  with. 

(Nos.  1  and  2)  It  has  already  been  pointed  out 
that  it  is  necessary  to  have  each  delivery  of  the  sizing 
ingredients  of  the  same  strength  and  quality.  Stress 
has  also  been  laid  on  the  necessity  of  making  exact 
measurements  and  weighings  of  each  ingredient, 
and  also  upon  the  necessity  of  correctly  treating  the 


368        The  Chemistry  and  Practice  of  Sizing. 


size,  so  that  conditions  Nos.  1  and  2  have  already 
been  discussed. 

(No.  3)  Uniform  Feed  of  Size. — The  uniform 
feed  of  the  size  to  the  "sow  box"  depends  on  the 
working  of  the  pump,  the  overflow  valve,  and  the 
self-feed  valve.  It  will  be  necessary  therefore  to 
describe  these  appliances  and  the  method  of  working 
them  in  full. 

Force  Pump  for  Pumping  Size. — For  "heavy" 
sizing  a  three-inch  pump  with  a  seven-inch  stroke, 
making  fifteen  to  twenty  strokes  per  minute,  will 
be  ample  for  one  machine.  Where  a  variety  of 
sizing  is  required  it  is  advisable  to  have  a  separate 
pump  for  each  tape  frame.  This  allows  each  machine 
if  necessary  to  be  on  a  different  kind  of  size. 
The  pump  ought  to  have  regulating  screws  pass- 
ing through  the  valve  lids  to  regulate  the  lift  of  the 
valves.  The  valve  itself  is  best  made  in  two  pieces, 
the  winged  or  lower  portion  screwing  into  the  upper 
part.  Old  friction  flannels,  or  winders'  listing 
should  be  cut  up  and  fixed  between  the  two  portions 
of  the  valve.  This  prolongs  the  life  of  the  valve 
face  and  of  the  seating.  The  weight  of  the  upper 
portion  of  the  valve  requires  to  be  increased  when 
pumping  very  heavy  size. 

An  illustration  of  a  size  pump,  attached  to  a 
beck,  is  shown  on  page  370. 

The  Sieve  Tap. — This  is  a  tap  fitted  between 
the  size  beck  and  the  pump.      Its  purpose  is  to 


Sieve  Tap — Over-flow  Valve.  369 


prevent  any  substance  likely  to  interfere  with  the 
working-  of  the  valves  getting  to  them.  The  sieve 
should  be  cleaned  out  at  least  once  a  day  in  order 
to  prevent  it  getting  clogged  up.  An  illustration  of 
a  sieve  tap  is  shown  below. 


Sieve  Tap. 

T.  Parkinson,  Britannia  Works,  Blackburn. 

The  Over-flow  Valve. — This  valve,  which  is 
shown  fitted  to  a  size  beck  on  page  370,  is  fixed 
between  the  pump  and  the  sizing  machine.     It  is 

used  in  order  to  keep  sufficient  pressure  on  the  size  in 

x 


370      The  Chemistry  and  Practice  of  Sizing. 

the  pipes  to  enable  it  to  reach  the  "sow"  box.  When 
the  "sow"  box  is  full,  or  the  self-feed  valve  nearly 


Size  Pump  and  Over-Flow  attached  to  Size  Mixing  Beck. 
T.  Parkinson,  Britannia  Works,  Blackburn. 

closed,  the  over-flow  valve  opens  and  allows  the 
surplus  size  to  return  to  the  beck  from  which  it  was 


Self- Feed  Valve. 


37* 


pumped.  The  valve  should  be  made  in  two  pieces 
as  recommended  for  the  pump  and  for  the  same 
reason.  Care  should  be  taken  to  keep  it  in  efficient 
working  order  and  not  to  over-weight  the  lever. 
If  the  lever  be  over- weighted  it  causes  unnecessary 
work  to  be  placed  on  the  pump. 

The  Self-Feed  Valve. — The  object  of  this 


Self-Feed  Valve. 
T.  Parkinson,  Britannia  Works,  Blackburn. 


valve,  an  illustration  of  which  is  shown  above,  is 
to  regulate  the  amount  of  size  entering  the  "sow" 
box  and  to  cut  off  the  supply  when  the  ' ' sow"  box 
contains  sufficient  for  working  requirements.  It  is 
connected  to  a  lever  holding  the  float  roller.  If  the 
pump  and  over-flow  valve  are  working  right  the 


372       The  Chemistry  and  Practice  of  Sizing. 

self-feed  valve  will  keep  a  constant  amount  of  size 
in  the  box.  The  rate  at  which  the  size  is  fed  to  the 
"sow"  box  should  be  kept  as  uniform  as  possible. 
To  ensure  this  the  valve  and  seating  must  be  kept 
in  good  working  order.  The  connection  between 
the  float  roller  lever  and  the  valve  lever  should  be 
firm,  and  the  nut  holding  the  regulating  clutch 
should  be  screwed  tight, 

By  paying  attention  to  the  foregoing  details  a 
uniform  feed  of  size  to  the  box  will  be  assured. 

(4)  Uniform  Boiling. — In  order  to  boil  the 
size  well  and  uniformly  it  is  usual  to  have  some 
form  of  boiling  apparatus  fixed  between  the  pump 
and  the  "sow"  box. 

The  amount  of  steam  required  to  boil  the  size 
varies  with  different  kinds  of  size,  and  the  rate  at 
which  it  is  being  used.  In  "pure"  sizing  the  amount 
of  size  put  on  the  yarn  is  very  small  compared  with 
the  amount  used  in  "heavy"  sizing.  In  the  latter 
case,  therefore,  the  size  remains  a  much  shorter 
time  in  the  "sow"  box  before  being  applied  to  the 
yarn  and  it  requires  more  steam  to  boil  it  thoroughly 
owing  to  its  greater  density.  On  this  account  it  is 
essential  that  the  size  should  be  boiled,  if  possible, 
before  entering  the  box.  Not  only  should  it  be 
raised  to  the  boiling  point  but  a  certain  time  should 
elapse  after  this  point  has  been  reached  in  order 
to  allow  the  whole  of  the  size  to  get  thoroughly 
"cooked."    Care  should  also  be  taken  to  have  it 


The  Practice  of 4  '  Tapeing ' 9 — Boiling  the  Size.  373 

boiling  in  every  portion  of  the  "sow"  box.  It  is 
quite  possible  to  have  size  boiling  in  one  portion  of 
the  box  and  not  in  another.  This  will  occur  if  any 
of  the  holes  in  the  "boil  pipes"  are  allowed  to  get 
made  up,  or  if  the  feed  pipe  does  not  deliver  the 
size  evenly  across  the  box. 

A  careful  examination  of  the  boil  pipes  should 
be  made  periodically  to  see  that  the  holes  are  not 
made  up.  If  any  of  the  holes  are  made  up  the  size 
will  be  imperfectly  boiled  in  their  proximity,  and 
uniform  boiling  will  be  impossible.  The  result  of 
passing  yarn  through  portions  of  size  insufficiently 
boiled  is  to  produce  a  damper  and  "stickier"  yarn 
than  that  which  is  passing  through  the  well  boiled 
portion  of  the  size.  This  extra  dampness  may 
cause  the  cloth  to  stick  on  the  beam,  or  it  may 
possibly  cause  the  cloth  to  mildew. 

It  has  already  been  stated  that  the  object  of 
boiling  the  size  is  to  burst  and  break  up  into  fine 
particles  the  granules  of  starch.  The  temperature 
at  which  these  granules  burst  is  considerably  below 
the  boiling  point  of  the  size,  if  the  whole  of  the  size 
be  at  a  uniform  temperature.  This  is  not  always 
the  case  however.  If  it  were  every  granule  of 
starch  would  be  broken  up  into  particles  so  small 
as  to  render  it  impossible  to  determine,  by  a 
microscopical  examination,  what  starches  had  been 
used  in  the  composition  of  the  size.  Yet  the 
authors  repeatedly  find,  when  examining  size  under 


374      The  Chemistry  and  Practice  of  Sizing. 

the  microscope  which  has  been  washed  from  cotton 
cloth,  many  unbroken  starch  granules.  These 
unbroken  granules  must  have  been  in  some  portion 
of  the  size  which  has  been  imperfectly  boiled, 
although  the  whole  of  the  size  may  have  appeared 
to  boik  Cloth  containing  a  large  amount  of 
unbroken  starch  granules  will  have  a  harsh  wiry 
feel  and  a  "  bad  cover." 

Size  Boiling  Pan. —  From  what  has  been  said 
as  to  the  importance  of  thoroughly  boiling  the 
size  it  will  be  evident  that  it  is  necessary  to  have  a 
good  form  of  boiling  pan  attached  to  the  tape 
frame.  The  authors  advise  a  deep  boiling  pan,  in 
which  the  outlet  for  the  size  is  a  few  inches  higher 
than  the  inlet,  in  preference  to  a  shallow  pan.  In 
a  deep  pan  the  steam  and  size  have  to  travel  a 
greater  distance  before  being  released  through  the 
holes  in  the  feed  pipe,  and  are  thus  longer  in  contact. 

The  capacity  of  a  pan  used  for  44 heavy"  sizing 
should  be  greater  than  one  used  for  "pure"  sizing 
because  a  larger  reserve  of  boiled  size  is  needed. 
This  is  because  the  size  is  used  up  more  quickly  in 
the  former  case.  If  a  small  pan  be  used  the  size 
would  get  forced  into  the  "sow"  box  before  it  was 
thoroughly  boiled.  With  a  large  pan  the  size  not 
only  gets  thoroughly  boiled,  but  the  boiling  is 
effected  with  the  minimum  of  steam. 

Simplicity  in  construction  is  the  most  important 
feature  to  consider  in  boiling  pans.    Those  shown  in 


Size  Boiling  Apparatus. 

George  Rushton,  Britannia  Brass  Works,  Darwen. 
Plate  XIII, 


Size  Boiling  Pans. 


375 


the  illustrations  are  amongst  the  best  on  the  market. 
They  are  simple  in  construction,  and  they  can  be 
made  in  various  sizes.  The  pan  illustrated  on 
plate  xiii,  consists  of  a  seamless  copper  cylinder  A. 
This  cylinder  is  5  feet  long,  and  it  is  fixed  vertically 
to  the  tape  frame  by  means  of  the  iron  angle  bracket 
H  in  a  convenient  position  near  the  "  sow  "  box.  The 
size  is  admitted  by  the  valve  C  from  the  self-feed 
valve  G,  and  steam  is  connected  to  the  valve  D. 
Immediately  the  size  is  admitted  into  the  cylinder  A 
it  is  operated  upon  by  steam  from  the  pipe  D.  In 
this  way  it  is  boiled  and  broken  up,  and  then  forced 
through  the  holes  in  mid-feather  B,  direct  into  the 
"sow"  box  by  the  copper  pipe  E. 

Another  form  of  boiling  pan,  attached  to  a  tape 
frame,  is  shown  in  the  illustration  on  page  376.  This 
pan  is  further  illustrated  by  the  diagram  on  page  377. 
It  is  constructed  entirely  of  brass  and  copper,  w7ith 
brazed  joints,  and  it  is  tested  to  60  pounds  pressure 
per  square  inch.  The  following  description  of  the 
diagram  will  explain  the  method  of  boiling  the  size 
in  this  pan :— The  size  enters  at  B  or  C,  as  may  be 
desired.  It  is  then  drawn  through  the  orifices  J.J, 
by  the  vacuum  caused  by  the  "steam  boiling  jet"  I, 
and  afterwards  driven  through  the  mixing  nozzle  G, 
It  then  passes  up  F,  and  strikes  the  deflecting 
head  H,  after  which  it  is  forced  down  again  and 
passes  the  baffle  plate  K.  The  size  then  re-enters 
at  J.J,  and  again  passes  the  "boiling  steam  jet"  I. 


376      The  Chemistry  and  Practice  of  Sizing. 

This  cycle  is  repeated  again  and  again  when  the 
pan  is  in  use,  and  in  this  way  the  size  gets 
thoroughly  boiled.  The  size  should  be  boiled 
before  the  tape  frame  is  started,  in  order  that  the 
ingredients  may  become  thoroughly  mixed  after 
standing  over  night  or  during  the  week-end. 


Boiling  Pan,  showing  44 Self-Feed  Valve"  (Float  Valve). 
C.  Parkinson,  Britannia  Works,  Blackburn. 


(5)  Uniform  Drying. — Uniform  drying  does 
not  mean  that  every  li  sort"  should  be  dried  alike.  To 
dry  <4 heavy"  sized  yarns  as  much  as  "pure"  sized 
would  be  a  great  mistake  as  this  would  cause 
too  much  breakage  of  the  former  when  the  sheet 


378       The  Chemistry  and  Practice  of  Sizing. 


of  yarn  was  separated  by  the  "  lease  rods."  It  may 
be  taken  as  a  rule  that  "pure"  sized  " sorts"  should 
receive  the  maximum  drying,  whilst  the  amount  of 
moisture  left  in  the  yarn  may  be  increased  as  the 
percentage  of  size  increases.  The  dryness  or 
dampness  of  the  yarn  depends  on  too  many  factors 
to  be  stated  with  any  degree  of  accuracy  in  a  book. 
At  the  same  time  each  ''sort''  is  best  dried  to  a 
degree  which  experience  has  shown  to  be  the  most 
suitable  for  producing  good  work.  Uniform  drying 
means  keeping  the  whole  of  the  beams  in  any  one 
particular  "sort"  dried  to  the  standard  which 
experience  has  proved  to  be  best  adapted  for  it.  If 
the  speed  at  which  the  machine  is  running  and  the 
pressure  of  steam  in  the  cylinders  be  well  adjusted 
one  to  the  other,  there  ought  to  be  no  difficulty  in 
obtaining  uniform  drying. 

It  may  be  advisable  to  point  out  that  the  per- 
centage of  moisture  in  the  warp  yarn,  when  converted 
into  cloth,  may  differ  from  the  amount  left  in  when 
it  leaves  the  tape  room.  Yarn  well  dried  but  sized 
with  a  "mixing"  containing  a  large  quantity  of 
chloride  of  magnesium  will  absorb  moisture  in  the 
weaving  shed.  On  the  other  hand  if  the  yarn  be 
left  damp  when  sized  with  a  "mixing'  containing  a 
small  quantity  of  chloride  of  magnesium,  or  none 
at  all,  it  will  lose  the  excess  of  moisture  in 
the  weaving  shed  and  probably  become  too  dry. 
The  amount  of  moisture  left  in  the  sized  yarn  in  the 


Practice  of 1 '  Tapeing 1 ' — Sensitiveness  of  Touch.  379 

majority  of  cloths  will  be  considerably  under  1 5  per 
cent.  Therefore,  all  substances  used  as  sizing 
ingredients  will  lose  any  excess  of  moisture  over 
this  amount  (unless  the  moisture  natural  to  them  be 
over  15  per  cent.)  before  being  converted  into  cloth. 

The  use  of  ingredients  containing  a  large  per- 
centage of  water  has  already  been  commented  upon, 
and  if  the  weight  which  is  retained  in  the  cloth  be 
taken  as  a  basis,  instead  of  the  weight  put  in  the  size 
mixing,  it  will  be  found  that  many  substances  which 
appear  to  be  cheap  are  really  very  dear. 

(6)  Sensitiveness  of  Touch. — This  is  one  of 
the  most  important  qualifications  of  a  really 
first-class  taper.  It  enables  him  to  judge  with 
certainty  by  feeling  the  yarn  of  "sorts"  he  is 
accustomed  to  : — 

(a) — If  the  yarn  be  under,  rightly,  or  overdried. 

({?) — If  the  size  be  sufficiently  well  boiled. 

(c)  — If  any  appreciable  variation  has  been  made 

in  the  size  i%  mixing." 

(d)  — If   the    yarn  be  much  under,    or  over- 

weighted. 

Every  taper  "  feels"  the  yarn  as  it  passes  from 
the  draw  roller  to  the  weavers  beam,  but  it  requires 
sensitive  finger  ends  and  a  receptive  brain  to  be  able 
to  transmit  this  information  from  his  fingers  to  his 
brain.  This  sensitiveness  can  be  acquired  only  by 
practical  experience  and  by  careful  attention  to  the 
various  "feels"  peculiar  to  sized  yarn.     The  yarn 


380      The  Chemistry  and  Practice  of  Sizing. 

should  be  felt  with  the  idea  of  deriving  some 
information,  and  not  merely  from  habit,  as  is  too 
often  the  case. 

Light  Weights  on  "  First  Beams." — The  first 
weaver  s  beam  run  at  the  beginning  of  a  day's  work 
is  more  liable  to  be  light  than  any  succeed- 
ing one.  This  is  due  to  several  causes.  In  the 
first  place  it  is  customary  to  wash  the  size  off  the 
copper  roller  after  the  machine  is  stopped.  The 
water  used  for  this  purpose  dilutes  the  size  in  the 
"sow"  box,  and  consequently  it  will  give  a  lower 
percentage  of  size  on  the  first  beam  which  goes 
through.  The  size  is  still  further  diluted  by  the 
condensation  of  the  steam  used  for  heating  the 
contents  of  the  "sow"  box.  To  counteract  this 
the  amount  of  size  left  in  the  box  should  be 
reduced  to  as  small  a  working  quantity  as 
possible  when  running  the  last  beam  of  a  days 
work.  If  this  be  done  a  larger  amount  of  fresh  size 
can  be  pumped  into  the  "sow"  box  when  com- 
mencing work  the  following  day.  It  is  possible  also 
to  avoid  the  use  of  water  for  washing  the  copper 
roller  if  the  machine  be  run  for  about  two  yards  on 
the  slow  motion  after  the  boil  taps  are  shut,  and  the 
dirty  portion  of  the  copper  roller  be  left  at  the  under 
side  when  "turning  back/' 

The  tape  frame  should  be  run  at  the  highest 
possible  speed  for  the  first  beam  until  the  full 
weight  of  size  is  assured.     The  faster  the  machine 


The  Practice  of  '"Tapeing" — Soft  Beams.  381 

is  ntn  the  greater  will  be  the  amount  .of  size  put 
on  the  yarn. 

Soft  Beams. — Not  only  are  light  weights  likely 
to  occur  on  the  first  beam,  but  there  is  always  a 
possibility  of  having  a  "soft  beam"  when  using 
"pure"  size.  This  is  especially  so  where  farina  is 
used.  As  previously  stated  this  starch  is  liable  to 
lose  its  adhesiveness  by  prolonged  boiling.  But  no 
matter  what  ingredients  are  used  the  extra  amount 
of  condensation  w7hich  takes  place  through  heating 
the  old  size  in  the  "sow"  box  tends  to  dilute  the 
size.  The  dilution  may  be  sufficient  to  reduce  its 
adhesiveness  to  such  an  extent  as  to  make  a  "soft 
beam,"  unless  care  be  taken  to  counteract  it.  The 
procedure  usually  adopted  is  to  mix  two  or  three 
pounds  of  sago  or  farina  in  a  small  quantity  of 
water,  and  add  this  to  the  contents  of  the  "sow" 
box  when  first  "boiling  up."  Care  must  be  exercised 
that  none  of  this  mixture  is  allowed  to  get  upon  the 
yarn,  or  upon  the  rollers,  as  it  might  cause  the 
threads  of  yarn  to  adhere  to  such  an  extent  as  to 
make  it  impossible  to  separate  them  when  the  yarn 
reaches  the  lease  rods. 

To  Obtain  a  Good  "Finish"  on  the  Yarn. — 
In  order  to  obtain  a  good  "finish"  on  the  yarn 
several  conditions  must  be  complied  with.  In  the 
first  place  the  size  must  be  well  boiled.  In  the 
second  place  the  copper  roller  must  be  sufficiently 
strong  to  run  true  when  heated.     In  the  third  place 


382      The  Chemistry  and  Practice  of  Sizing. 

the  finishing  roller  must  be  of  sufficient  weight 
to  press  the  size  well  into  the  spaces  between  the 
individual  fibres  of  which  a  thread  is  composed,  and 
the  flannels  and  fent  on  this  roller  should  be  free 
from  cuts  or  "  scrimps. n 

The  weight  of  the  finishing  roller  depends 
to  a  certain  extent  on  the  class  of  work  for  which 
it  is  to  be  used.  For  ordinary  work  a  weight 
of  six  or  seven  pounds  per  inch  of  width  is  ample, 
but  for  "  heavy sizing  a  roller  weighing  eight  pounds 
per  inch  would  be  better.  If  a  heavy  roller  be 
employed  it  will  be  necessary  to  make  the  "size  ' 
rather  stronger  in  order  to  obtain  the  desired  weight 
than  it  would  be  if  a  lighter  roller  were  used.  This 
matter  has  already  been  discussed  on  page  296. 

"  COLOURED  "  TAPEING. 

For  coloured  work  it  is  usual  to  have  an  extra 
"sow'*  box,  commonly  termed  the  "coloured"  box. 
An  illustration  of  one  is  shown  on  page  383.  It  is 
simply  a  "sow"  box  in  miniature,  and  is  used 
only  when  the  grey  and  coloured  yarns  are  not 
sized  alike.  If  the  grey  yarn  has  to  be  heavily 
sized  whilst  the  coloured  yarn  has  to  be  sized 
sufficiently  to  make  it  weave  only,  then  the  extra 
"sow"  box  will  be  necessary. 

The  "coloured"  box  should  be  fixed  either  over 
the  small  cylinder,  or  in  front  of  the  "sow"  box.  If 


384      The  Chemistry  and  Practice  of  Sizing, 

fixed  over  the  small  cylinder  it  is  not  very 
convenient  for  the  "taper"  when  running  coloured 
"sorts,'  but  it  is  more  out  of  the  way  when  running 
plain  "sorts"  only.  In  this  position  the  coloured 
yarn  is  not  so  subject  to  "twirling"  as  it  is  if  the  box 
be  fixed  in  front  of  the  "sow"  box,  but  there  is  more 
liability  to  damage  if  the  size  boils  over. 

When  the  "coloured"  box  is  fixed  on  the  front 
of  the  "sow"  box  the  immersion  rollers  in  both 
"sow"  boxes  can  be  arranged  to  wind  up  or  down 
simultaneously. 

The  copper  roller  in  the  "coloured"  box  derives 
its  motion  from  the  side-shaft  by  means  of  an  upright 
shaft  driven  with  bevel  wheels.  Another  pair  of 
bevel  wheels  and  a  pair  of  spur  wheels  on  the  top  of 
the  upright  shaft  complete  the  driving  mechanism. 
The  spur  wheels  can  be  used  as  ''change  wrheels" 
for  altering  the  speed  of  the  copper  roller.  These 
change  wheels  would  be  better  if  they  contained  more 
teeth  than  they  are  made  with  at  present.  This 
would  allow  slight  alterations  to  be  made  in  the 
speed.  These  alterations  are  essential  in  order  to 
keep  the  coloured  yarn  at  the  right  tension  at  each 
side  of  the  box.  If  the  yarn  be  slack  between  the 
backbeam  and  the  box,  and  an  alteration  of  one 
tooth  is  made  in  a  driving  change  wheel  which  has 
seventy  teeth,  the  copper  roller  will  afterwards  run 
seventy-one  yards  in  the  same  time  in  which  it 
previously  ran  seventy.     This  may  be  too  much, 


1 '  Coloured 1 '  Tapezng. 


385 


and  the  yarn  will  tighten  at  the  side  which  was 
previously  slack,  and  be  much  too  slack  at  the  other 
side.  An  arrangement  which  would  allow  of  a 
change  of  one  yard  in  two  to  three  hundred  yards 
would  be  preferable. 

The  above  difficulty  is  always  experienced  with 
backbeams  having  grey  yarn  in  the  middle  and 
coloured  yarn  at  the  sides.  If  particular  attention 
be  paid  to  the  number  of  empty  dents  allowed  in 
the  warping  mill  the  grey  and  coloured  yarns  can 
be  arranged  to  unwind  off  the  backbeam  at  the 
right  speeds. 

In  the  sizing  of  coloured  bordered  dhooties, 
where  a  fair  amount  of  size  on  the  grey  yarn  is 
required,  the  grey  yarn  should  be  taped,  if  possible, 
so  as  to  leave  it  damper  than  the  coloured 
yarn.  This  is  essential  for  several  reasons.  In  the 
first  place  heavily  sized  grey  yarn  requires  more 
moisture  than  pure  sized  yarn  in  order  to  enable  it 
to  weave  well.  In  the  second  place,  unless  the 
coloured  yarn  is  well  dried,  there  is  a  danger  of 
mildew  developing.  This  is  a  frequent  cause  of 
damage  in  coloured  bordered  dhooties  because  the 
size  for  the  coloured  yarns  does  not,  as  a  rule,  contain 
preservative  substances.  The  mildew  may  not  show 
on  the  coloured  yarn  in  every  case,  but  it  frequently 
"marks  off"  on  the  grey  yarn  after  it  has  been 
packed.  This  matter  is  discussed  in  detail  in  the 
chapter  on  mildew. 

Y 


386      The  Chemistry  and  Practice  of  Sizing. 

If  the  ordinary  way  of  threading  the  yarn  round 
the  cylinders  be  employed,  it  is  practically  impossible 
to  leave  more  moisture  in  the  grey  yarn  than  in  the 
coloured  yarn,  as  the  latter  goes  over  the  big  cylinder 
on  the  top  of  the  grey  yarn.  Under  such  conditions 
the  grey  yarn  is  always  dryer  than  the  coloured. 

There  are  two  methods  by  which  this  defect 
may  be  remedied.  The  first,  which  has  already  been 
mentioned  on  page  329,  consists  in  arranging  for  the 
coloured  yarn  to  run  next  to  the  surface  of  the 
drying  cylinders.  This  arrangement,  which  is 
shown  in  the  diagram  on  page  387,  is  brought 
about  as  follows  : — 

A  number  of  guide  rollers  are  fixed  in  such  a 
manner  that  the  coloured  yarn  travels  from  the 
copper  roller  for  a  short  distance  down  the  front 
of  the  big  cylinder.  It  is  then  turned  back  by 
passing  over  and  under  a  guide  roller.  This 
transfers  the  coloured  yarn  from  the  upper  surface 
to  the  lower  surface  of  the  grey  ''sheet"  of  yarn, 
and  thus  brings  it  in  direct  contact  with  the  surface 
of  the  big  cylinder. 

After  being  turned  back  at  this  point  the  yarn 
is  brought  round  the  big  cylinder  in  the  opposite 
direction  to  that  usually  taken  until  it  gets  well 
round  to  the  front  of  the  cylinder.  Here  another 
guide  roller  is  fixed  and  the  yarn  goes  round  it 
after  leaving  the  cylinder.  Other  guide  rollers 
are  arranged  to   convey  the  yarn  to  the  small 


388      The  Chemistry  and  Practice  of  Sizing. 

cylinder,  which  is  threaded  in  the  usual  way,  From 
the  small  cylinder  it  passes  to  the  headstock. 

The  second  method  adopted  for  properly  drying 
the  coloured  yarn  is  to  use  an  extra  drying  cylinder. 
This  cylinder  is  usually  about  eighteen  inches  in 
diameter,  and  it  is  driven  positively  in  the  same 
manner  as  the  mechanism  of  the  ''coloured"  box. 
This  is  done  in  order  to  prevent  any  extra  tension 
being  put  on  the  coloured  yarns.  This  extra 
cylinder  may  be  fixed  either  over  the  small  cylinder 
or  over  the  headstock.  In  the  former  case  two 
guide  rollers  are  arranged  so  as  to  give  the  coloured 
yarn  as  much  lap  round  the  "coloured"  cylinder  as 
possible.  The  coloured  yarn  is  thus  partially  dried 
before  it  passes  round  the  ordinary  drying  cylinders. 
When  the  "  coloured"  cylinder  is  placed  over  the 
headstock,  the  coloured  yarn  receives  an  extra 
drying  after  leaving  the  ordinary  cylinders. 

The  pressure  of  steam  in  the  ordinary  cylinders 
and  in  the  "  coloured "  cylinder  can  be  varied. 
Therefore  if  the  pressures  in  the  cylinders  and  the 
speed  of  the  machine  are  regulated  the  grey  yarn 
can  be  wound  on  the  weaver  s  beam  damp,  whilst 
the  coloured  is  dry.  For  all  shirting  dhooties  this 
is  a  decided  advantage. 

The  position  occupied  by  the  coloured  back- 
beam  in  the  creel  varies.  Where  only  one  coloured 
beam  is  required,  it  may  occupy  the  first,  second  or 
third  place.     If  the  second  place  be  used,  a  roller  is 


* '  Coloured ' '  Tapeing. 


389 


fixed  under  it  to  support  the  yarn  between  the  third 
and  the  first  beams.  The  authors  prefer  the  second 
place  as  the  "taper"  is  better  able  to  control  the 
rate  at  which  the  coloured  beam  "runs." 

One  of  the  things  to  be  guarded  against  in 
coloured  work  is  the  "twirling"  of  the  coloured  yarn. 
This  takes  place  between  the  "coloured"  box  and  the 
drying  cylinder  when  the  frame  is  stopped  or  when 
it  is  on  the  slow  motion.  The  sized  ends  twirl  round 
one  another  when  wet,  and  when  they  are  dried  it  is 
almost  impossible  to  separate  them  without  breaking. 
This  twirling  is  usually  caused  by  the  coloured  yarn 
being  slack,  or  unsupported,  for  too  great  a  distance. 
The  use  of  thick  size  for  the  coloured  yarn  has 
also  a  tendency  to  cause  it. 

To  prevent  "twirling,"  rollers  are  usually 
employed  to  bring  the  coloured  and  grey  "sheets" 
together  as  soon  as  possible  after  the  coloured 
yarn  has  left  the  "sow"  box.  The  "coloured  sheet" 
must  be  kept  tight,  and  the  mixing  used  for  sizing 
it  should  be  composed  of  such  ingredients  as  will 
give  a  very  thin  "mixing,"  and  yet  be  strong  enough 
to  make  the  yarn  weave  well 

When  the  combined  sheets  of  grey  and  coloured 
yarn  reach  the  headstock  the  coloured  yarn  is 
separated  from  the  grey  yarn  by  means  of  a  roller, 
which  is  fixed  a  few  inches  higher  than  the  measuring 
roller.  If  the  whole  of  the  coloured  yarn  be  intended 
for  the  borders,  it  is  taken  to  each  side  of  the  wraith, 


390      The  Chemistry  and  Practice  of  Sizing. 

the  teeth  of  which  are  made  about  half-an-inch 
longer,  as  previously  described  on  page  351. 

Two  wires  are  arranged  parallel  with,  and  in  front 
of  the  wraith,  and  just  behind  the  sheeting  rollers. 
These  wires  are  used  for  the  purpose  of  supporting 
and  steadying  the  pins  which  are  employed  for 
separating  the  coloured  stripes  from  each  other,  thus 
keeping  them  in  their  places  on  the  weaver's  beam. 

It  would  probably  serve  no  useful  purpose  to 
go  into  every  detail  in  connection  with  " coloured" 
or  plain  "tapeing."  Sufficient  has  already  been 
written  to  enable  those  who  never  have  had  any 
practical  experience  in  running  a  machine,  but  who 
are  in  positions  requiring  a  knowledge  of  "tapeing," 
to  obtain  an  insight  into  the  most  important  details 
of  the  tape  frame,  and  the  process  of  tape-sizing. 


Ball  or  Warp  Sizing. 


39i 


Chapter  IX. 


Bally  or  Warp  Sizing. 


The  Tinting  of  Yarns  in  the  Process 


HE  operation  known  as  ball  or   warp  sizing 


X  is  confined  almost  entirely  to  three  classes 
of  yarns,  viz  : — 

1  st. — Yarns  for  fancy  coloured  goods. 
2nd. — White  yarns. 

3rd. — Grey  yarns  of  low  counts  where  a  large 
amount  of  size  has  to  be  incorporated 
with   the   yarn,  and  where  a  certain 
"feel"  and  appearance  is  required. 
Ball  sizing  is  a  process  particularly  adapted  for 
sizing  coloured  yarns  as  will  be  explained  later,  but 
for  ordinary  grey  yarns,  and  for  grey  yarns  of  fine 
counts,  it  cannot  compete  with  tape  sizing.     In  ball 
sizing  three  separate  processess  are  involved,  viz. : — 
Sizing,   Drying,  and   Beaming,  whereas    in  tape 


BALL  OR  WARP  SIZING. 


392        The  Chemistry  and  Practice  of  Sizing. 

sizing  the  whole  of  these  processes  are  performed 
in  one  operation. 

There  are  instances,  however,  where  certain 
markets  require  heavily  sized  grey  cloth  which  must 
possess  a  peculiar  leathery  "  feel  and  appearance. 
This  4 'feel"  and  appearance  is  characteristic  of  ball 
sized  yarns,  and  it  cannot  be  imitated  on  the  tape 
frame.  So  long,  therefore,  as  there  is  a  demand 
for  such  cloth  there  will  be  a  demand  for  ball  sized 
grey  warps. 

Ball  sizing  produces  a  round  and  very  pliable 
yarn,  and  it  is  also  claimed  by  ball  sizers  that  they 
can  produce  a  yarn  which  will  look  and  "feel" 
several  counts  heavier  than  if  tape  sized.  There 
is  a  considerable  amount  of  truth  in  this  statement 
inasmuch  as  the  threads  are  not  flattened  as  they 
are  when  tape  sized.  The  ingredients  used  in  the 
size  are  somewhat  different  to  those  employed  in 
tape  sizing  and  this  has  a  considerable  effect  on  the 
results.  For  one  thing  it  is  customary  to  use  soluble 
mineral  substances,  such  as  Epsom  salts,  to  a  greater 
extent  than  it  is  in  tape  sizing.  Chloride  of  zinc  is 
also  employed  to  a  greater  extent  as  a  weighting 
ingredient,  whereas  in  tape  sizing  it  is  usually 
employed  as  an  antiseptic  for  the  prevention 
of  mildew  only.  Soluble  substances  of  this 
description  tend  to  swell  the  yarn. 

Apart  altogether  from  the  ingredients,  the 
difference  in  the  nature  of  the  operations  affects  the 


Ball  or  Warp  Sizing. 


393 


character  of  the  yarn.  In  tape  sizing  the  yarn  is 
run  through  the  size,  then  through  the  nip  of  the 
copper  and  finishing  roller  and  immediately  dried 
in  the  form  of  a  flat  sheet  on  the  drying  cylinders. 
From  the  cylinders  it  passes  to  the  weaver's  beam 
on  which  it  is  wound.  The  whole  of  these 
operations  naturally  tend  to  flatten  out  the  threads. 

In  ball  sizing  every  operation  tends  to  preserve 
the  roundness  of  the  threads  and  render  them 
pliable.  The  yarn  is  passed  through  the  size  in  the 
form  of  a  rope  instead  of  in  the  form  of  a  flat  sheet. 
It  is  afterwards  dried  on  the  drying  cylinders.  The 
latter  operation  is  a  distinct  and  separate  process, 
and  it  is  not  usually  carried  out  immediately  after 
the  yarns  have  been  sized.  The  object  aimed  at 
in  drying  is  to  leave  a  certain  amount  of  moisture  in 
the  middle  of  the  warp.  As  the  warps  are  not 
beamed  for  some  considerable  time  after  sizing  and 
drying  the  moisture  has  a  chance  of  becoming 
evenly  distributed  throughout  the  mass  of  threads. 
This  has  the  effect  of  giving  to  each  individual 
thread  a  mellow  pliable  condition. 

From  the  difference  in  the  operations  it  will  be 
at  once  apparent  that,  although  tape  sizing  has  many 
advantages  over  ball  sizing  as  far  as  speed  and 
economy  are  concerned,  there  are  yet  many  purposes 
where  the  latter  process  can  be  successfully  carried 
on  which  can  never  be  superseded  by  tape  sizing. 
The  sizing  of  coloured  yarns  for  fancy  coloured  woven 


394       The  Chemistry  and  Practice  of  Sizing. 

goods  is  a  case  in  point.  It  would  be  quite  impossible 
to  successfully  size  such  yarns  on  the  tape  frame. 
There  are  many  reasons  for  this.  In  the  first 
place  it  is  necessary  to  run  each  colour  separately 
on  account  of  the  "bleeding"  of  the  different  colours. 
In  the  second  place  coloured  sizing  is  made  up 
more  of  a  succession  of  small  lots  which  could  not 
possibly  be  treated  in  an  economical  manner  on  the 
tape  frame.  It  is  rarely  the  case  that  such  lengths 
of  yarn  are  run  as  for  standard  grey  cloths  or 
bleaching  cloths.  In  the  third  place  warps  containing 
very  few  "ends"  can  be  successfully  treated  in  ball 
sizing  because  the  yarn  may  be  doubled  as  often  as 
necessary  to  get  a  warp  of  the  right  thickness.  Thus, 
instead  of  the  warp  being  passed  through  the  size  at 
its  full  length  it  can  be  treated  in  its  reduced  length. 
Doubling  the  warp  makes  no  difference  to  the  results 
or  to  the  after  process  of  beaming. 

There  are  certain  firms  who  have  a  regular  trade 
for  striped  warps  in  standard  colours.  Such  firms 
will  dye  and  size  warps  containing  2,000  to  3,000 
"ends"  of  each  of  these  colours  for  stock.  When 
they  receive  an  order  for  any  design  they  split  them 
up  into  as  many  "ends"  as  may  be  required  to  make 
the  design.  Thus  a  weavers  beam  may  require,  say, 
1,000  "ends"  of  white  yarn,  and  100  to  200  "ends" 
each  of  various  coloured  yarns,  such  as  red,  pink, 
green,  heliotrope,  brown,  etc.,  and  these  would  be 
taken  from  stock. 


Ball  or  Warp  Sizing.  395 
• 

A  firm  having  a  trade  of  this  kind  would  avoid 
the  trouble  of  dyeing  and  sizing  small  lots  of  warps, 
Not  only  would  the  shades  be  more  exact  for  repeat 
orders,  but  the  yarn  would  be  in  better  condition 
for  weaving  after  beincr  stored  for  some  little  time. 

From  what  has  been  said  it  will  be  seen  that, 
although  some  firms  can  arrange  to  deal  with  large 
warps,  it  is  not  always  possible  to  do  this,  and  to 
try  and  treat  small  lots  of  warps  on  the  tape  frame, 
apart  from  the  question  of  the  "  bleeding"  of  the 
colours,  would  be  economically  impossible, 

As  a  rule  the  manufacturer  who  uses  ball  sized 
warps  does  not  size  them  himself,  but  buys  them 
from  the  dyer.  As  a  general  thing  this  is  an 
advantageous  arrangement  for  the  manufacturer,  as 
he  is  not  only  saved  the  trouble  of  sizing  but  also  the 
trouble  of  dyeing,  and  to  carry  out  the  operations 
properly  he  would  require  to  be  a  practical  dyer  as 
well  as  a  sizer  and  manufacturer.  It  will  be  readily 
understood  that  if  the  manufacturer  purchased 
"unsized"  coloured  yarns  to  match  those  in  a  piece 
of  cloth,  he  would  be  liable  to  alter  the  shade  when 
they  were  sized.  The  dyer  always  takes  this  into 
consideration,  and  arranges  that  the  yarns  shall  be 
dyed  so  as  to  come  up  the  right  shade  when  sized. 
The  manufacturer  is  thus  relieved  of  most  of  the 
responsibility  as  far  as  shade  of  colour  is  concerned. 

Although  it  is  an  advantage  in  many  ways  to 
leave  the  sizing  in  the  hands  of  the  public  dyer 


396      The  Chemistry  and  Practice  of  Sizing. 

there  are  also  disadvantages.  In  the  first  place 
the  manufacturer  has  to  use  such  yarn  as  may  be 
supplied  to  him  by  the  dyer,  and  if  he  is  desirous  of 
getting  brighter  shades  he  has  to  depend  upon 
other  people.  A  manufacturer  may  require  not 
only  an  improvement  in  his  colours  and  his  sizing, 
but  he  may  want  to  develop  a  speciality  business. 
In  such  circumstances  as  these  he  will  not  want 
other  people  to  know  what  he  is  doing,  and  it  will 
be  better  that  he  should  dye  and  size  his  own  yarn. 
This  may  entail  the  putting  down  of  a  bleaching 
plant  as  wTell  as  a  plant  for  dyeing  and  sizing. 
There  is  no  doubt  that  this  matter  will  have 
to  be  carefully  considered  by  English  manu- 
facturers of  coloured  goods.  Most  of  the  com- 
petition in  the  cotton  trade  in  this  country  is  in 
this  class  of  cloth,  and  until  recently  Continental 
firms  were  beating  the  English  manufacturer  out 
of  the  field  because  they  were  putting  a  better 
dyed  cloth  on  the  market.  The  colours  were 
brighter  and  clearer  than  anything  we  were  getting. 
The  result  of  this  competition  has  been  that  several 
manufacturers  have  recently  equipped  their  works 
with  bleaching,  dyeing,  and  sizing  machinery, 
and  they  are  now  turning  out  better  work  than 
their  competitors  from  the  Continent.  This  is  a 
matter  which  all  makers  of  specialities  in  coloured 
goods  should  consider  very  seriously,  as  they 
are  only  certain  of  getting  exactly  what  they  want 


Ball  Sizing  Plant. 


397 


by  having  the  control  of  the  whole  of  the  processes 
in  their  own  hands. 

BALL  SIZING  PLANT. 

The  apparatus  used  in  '  ball  sizing  differs 
considerably  from  that  used  in  tape  sizing,  but  the 
method  of  mixing  the  sizing  ingredients  together 
is  practically  the  same  in  both  cases. 

A  model  arrangement  of  a  ball  sizing  plant,  of 
which  the  following  are  the  essential  parts,  is  shown 
on  plate  xiv.  : — 

The  Mixing  Becks. 

The  Boiling  Pan  or  Beck  (used  for  boiling 

the  size  for  heavily  sized  grey  yarns). 
The  Clay  Pan. 

The    Sizing    Machine,    with    its  various 
appliances. 

The  Drying  Machine. 
Mixing  Becks. — Several  becks  are  required 
for  mixing  the  sizing  ingredients  together,  the 
number  depending  upon  the  variety  of  the  sizing 
undertaken.  At  least  two  becks  are  required 
for  storing  a  standard  mixture  of  flour  and  water. 
A  third  beck  may  be  required  for  mixing  the  various 
ingredients  together,  although  very  often  the 
"mixing"  is  made  in  the  size  box  without  using  a 
mixing  beck  at  all.  Each  beck  should  be  fitted  with 
agitators,  similar  to  those  described  on  page  271. 


398      The  Chemistry  and  Practice  of  Sizing. 

The  becks  for  the  flour,  and  the  mixing  beck 
should  be  arranged  on  different  levels,  so  that  the 
flour  in  steep  may  be  run  into  the  mixing  beck 
below.  The  mixing  beck  should  be  on  a  higher 
level  than  the  sizing  machine,  so  that  the 
completed  "  mixing"  may  be  run  into  the  size 
box.  Unless  this  arrangement  be  carried  out  it 
would  be  necessary  to  employ  pumps,  or  ejectors,  to 
raise  the  flour  and  the  size  to  the  necessary  levels. 

Boiling  Pan  or  Beck.  —  A  boiling  pan  or  beck 
is  necessary  for  heavily  sized  grey  yarns  where 
China  clay  is  an  ingredient  of  the  ''mixing/'  It 
has  been  previously  mentioned  that  it  is  necessary 
to  boil  China  clay  for  two  or  three  hours,  in  order 
to  break  it  up  into  fine  particles.  Where  the 
"mixing"  is  a  small  one  this  pan  may  be  used  for 
mixing  the  ingredients  together,  and  boiling  them 
previous  to  their  use  in  the  size  box. 

THE  SIZING  MACHINE. 

The  sizing  machine,  an  illustration  of  which  is 
shown  on  page  399,  consists  of  the  following 
essential  parts: — 

The  Size  Box,  with  its  various  appliances. 
The  Squeezing  Apparatus. 
The  Delivery  Winch. 
Size  Box. — The  size  box  is  constructed  generally 
of  wood,  but  sometimes  entirely  of  iron.  Occasionaly 


Warp  Sizing  Machine.  399 

it  is  made  of  brass,  and  finished  off  on  the  outside 
with  planished  steel  plates,  packed  with  non- 
conducting material.  It  is  fitted  with  a  number  of 
copper  brackets,  in  which  are  a  number  of  eyelets. 


Warp  Sizing  Machine. 


Corresponding  to  each  eyelet  is  a  copper  roller. 
Both  the  eyelets  and  the  rollers  are  placed  below 
the  level  of  the  size. 

The  size  box  is  fitted  with  i-inch  copper  pipes, 
through  which  steam  is  passed  for  the  purpose  of 


400      The  Chemistry  and  Practice  of  Sizing. 

boiling  the  size.  These  pipes  are  perforated  with 
one  row  of  holes,  which  should  face  upwards  so  as 
to  avoid  "  blowing"  the  warp  as  it  travels  through 
the  box.  The  pipes  are  usually  arranged  in  three 
rows  at  the  bottom  of  the  box.  The  steam 
to  the  two  side  pipes  is  controlled  by  one 
valve,  whilst  the  middle  pipe  is  controlled  by  a 
separate  one.  This  allows  the  sizer  to  use  more 
or  less  steam  as  required.  When  running  it  is 
customary  to  use  the  two  side  pipes  only, 
whilst  the  middle  one  is  used  when  boiling-  the 
size  previous  to  the  warp  being  run  through. 
This  arrangement  is  carried  out  to  avoid  the 
danger  of  the  steam  from  the  middle  pipe  blowing 
on  to  the  warp. 

In  the  larger  size  boxes,  the  size  is  first  boiled 
in  a  separate  compartment  before  it  comes  in 
contact  with  the  warp.  The  boiled  size  passes 
into  the  main  compartment  under  the  dividing 
partition,  which  is  fixed  so  as  to  allow  a  space 
between  the  bottom  of  the  partition  and  the 
box. 

The  size  box  is  made  in  various  lengths,  accord- 
ing  to  wThether  it  be  intended  to  be  used  for  one 
class  of  yarn  continuously,  or  for  small  lots  of 
coloured  work.  For  coloured  work  it  may  range 
from  five  feet  in  length  upwards,  whilst  for  heavy 
grey  sizing  it  is  usually  constructed  from  eighteen 
feet  to  twenty-twTo  feet  long. 


Ball  or   Warp  Sizing. 


401 


In  heavy  grey  sizing  a  large  size  box  is  always 
used,  and  in  order  to  obtain  the  necessary  weight  of 
size  on  the  yarn,  the  warp  is  arranged  to  traverse  the 
box  in  the  manner  show7n  on  plate  xiv% 

The  length  of  the  size  box,  and  the  number  of 
times  the  warp  traverses  it,  together  with  the 
rate  at  which  the  machine  is  run,  determines  the 
length  of  time  the  yarn  is  immersed  in  the  size. 
In  some  cases  the  warp  is  arranged  to  traverse  the 
box  twice  or  three  times.  It  may  be  taken  as  a 
general  rule  that  the  longer  the  warp  is  immersed  in 
the  size  the  better  will  be  the  result. 

It  is  not  always  convenient  to  give  coloured 
yarns  a  very  long  immersion,  because  each  colour 
of  yarn  has  to  be  sized  separately,  and  very 
often  fresh  size  has  to  be  made  for  each  "sort," 
especially  if  they  are  light  shades.  A  small  sizing 
machine  is,  on  this  account,  more  economical  than 
a  large  one  for  small  lots  of  "coloured"  work. 

At  the  same  time  it  should  be  understood  that  it 
is  not  necessary  to  waste  any  size  even  when  dealing 
with  small  lots  of  various  coloured  warps.  It  is 
entirely  a  question  of  management.  Where  it  is 
possible  it  should  be  arranged  for  certain  colours 
to  follow  each  other  through  the  size  box.  For 
instance,  if  light  pinks  are  sized  first  they  may 
be  followed  by  dark  pinks,  reds,  and  maroons. 
The  same  arrangement  can  be  carried  out  with 

other  colours;  light  blues  followed  by  dark  blues; 

z 


402       The  Chemistry  and  Practice  of  Sizing. 


light  greens  followed  by  dark  greens  ;  cream  shades 
by  buffs,  yellows,  gold,  orange,  brown,  etc. 

If  it  be  inconvenient  to  run  the  shades  as  here- 
with described,  the  size  from  one  lot  of  warps  should 
not  be  thrown  away,  but  should  be  run  into  a  well 
or  reserve  tank.  This  size  may  be  used  for  any  very 
dark  colours  or  for  blacks.  As  a  matter  of  fact,  if 
the  size  has  been  properly  made  from  suitable 
ingredients  it  will  be  in  better  condition  after  it  has 
been  agitated  by  the  passage  of  the  warps,  and 
pressed  by  the  nip  of  the  squeezing  rollers,  and 
after  it  has  been  well  boiled,  than  it  was  when 
freshly  prepared.  Fresh  size  is  <4raw,"  and  does 
not  give  the  same  " mellowness"  to  the  warps  as 
that  which  has  been  well  worked  and  boiled.  Not 
only  is  this  the  case,  but  old  size  does  not 
require  as  much  tallow  as  new  size  to  produce 
the  same  pliability  in  the  yarn.  Experience 
has  proved  that  size  improves  as  the  boiling  is 
continued,  and  the  dark  coloured  warps  which  have 
followed  in  the  same  size  as  the  light  shades  are 
better  in  every  way.  It  is  important  that  the  old 
size  should  be  "strengthened  up"  with  a  little  new 
size  occasionally  on  account  of  the  dilution  which 
takes  place  in  the  box  through  condensation 
from  the  steam  used  for  boiling  purposes.  The 
longer  the  boiling  is  continued  and  the  more 
condensation  (and  consequent  dilution)  will  take 
place.      For  this  reason  it  is  better  to  have  as 


Ball  Sizing —  The  Squeezing  Apparatus.  403 

small  a  volume  of  size  as  possible  in  the  box 
when  first  starting. 

In  ball  sizing  it  is  not  customary  to  have 
an  automatic  flow  of  size  to  the  machine.  The 
addition  of  fresh  size  from  the  mixing1  beck  is  made 
through  a  pipe  fitted  with  a  plug  tap.  It  will  readily 
be  seen  that  this  arrangement  is  sufficient  on 
account  of  the  capacity  of  the  box,  which  may  hold 
anything  from  two  or  three  hundred  to  a  thousand 
gallons. 

SQUEEZING  APPARATUS. 

The  squeezing  apparatus,  which  consists  of  two 
heavy  rollers  fitted  with  levers  and  weights,  is  used 
for  squeezing  the  superfluous  size  from  the  yarn  as 
it  leaves  the  size  box. 

The  Top  Roller, — The  top  roller,  which  is 
acted  upon  by  levers  and  weights,  is  generally 
made  of  sycamore.  This  roller  should  be  about 
24  inches  in  diameter  when  new  (according  to 
the  size  of  the  machine),  and  it  should  be  lapped 
with  a  linsey  lapping.  The  best  form  of  lapping 
has  a  linen  warp  and  a  woollen  weft.  The  lapping 
is  about  40  to  50  yards  long  when  new.  As  the 
outside  lap  gets  worn  it  is  cut  off  so  as  to  present  a 
fresh  surface  to  the  warp. 

In  covering  the  roller  the  end  of  the  flannel  is 
first  tacked  on,  after  which  it  is  wound  as  tightly  as 
possible,  and  fastened  to  the  roller  by  means  of 


404 


The  Chemistry  and  Practice  of  Sizing. 


lone  nails  which  are  driven  through  the  sides  of  the 
roll  of  flannel  into  the  wood. 

At  the  present  time  iron  rollers  are  being  used  in 
the  place  of  sycamore.  These  rollers  are  fitted  with 
wooden  plugs  in  order  to  allow  the  "lapping"  to  be 
fixed  with  nails. 

The  top  roller  rests  on  the  bottom  roller  and 
works  in  a  slot.  It  is  not  driven  direct  but  derives 
its  motion  from  the  bottom  roller. 

The  Bottom  Roller, — The  bottom  roller  is 
made  of  cast  iron,  fixed  upon  a  wrought  iron  or  a 
steel  shaft.  It  is  usually  about  24  inches  in  diameter 
and  about  20  to  22  inches  long.  This  roller  runs 
in  brackets  and  it  is  either  driven  by  means  of  spur 
wheels  or  direct  from  the  shafting.  The  bottom 
roller  is  usually  run  without  lapping  of  any 
description. 

The  pressure  on  the  squeezing  rollers  is  regulated 
by  the  levers  and  weights,  which  are  placed  at  each 
end  of  the  top  roller. 

The  correct  regulation  of  the  pressure  on  the 
squeezing  rollers  is  a  matter  of  the  greatest  importance 
in  ball  sizing.  The  amount  of  pressure  to  be  used 
depends  upon  the  class  of  yarn  undergoing  treat- 
ment; but  it  may  be  taken  as  a  general  rule  that  the 
warps  should  not  be  left  too  wet.  In  this  condition 
they  would  turn  up  too  boardy,  and  in  many  cases 
they  would  be  found  matted  together  after  drying 
on  the  cylinders. 


Ball  or  Warp  Sizing. 


405 


To  ascertain  whether  the  yarns  are  correctly 
sized  and  sufficiently  squeezed  the  sizer  twists  the 
warp  between  his  fingers  and  thumbs.  This  test 
enables  him  to  form  a  correct  judgment  as  to  the 
condition  of  the  warp.  If  it  has  been  sufficiently 
dried  by  the  squeezing  rollers  he  should  be  able  to 
"feel"  the  size  but  not  able  to  squeeze  more  than  a 
small  quantity  of  it  from  the  warp.  The  "feel"  of 
the  warp  will  enable  him  to  judge  whether  the  size  is 
sufficiently  "mellow."  If  the  size  sticks  to  his  fingers 
like  elue  it  shows  that  there  is  not  sufficient  tallow  in 
the  "mixing."  This  method  of  testing  may  appear 
to  be  rough  and  ready  and  somewhat  of  the  nature 
of  "rule  of  thumb,"  but  when  applied  by  an  expert 
sizer  it  is  sufficient  to  enable  him  to  determine  the 
condition  of  the  warp. 

Much  better  results  can  be  obtained  by  using  a 
strong  size,  and  squeezing  the  warps  well,  than  by 
using  a  weaker  size,  and  leaving  the  warps  "wet." 
Coarse  counts  of  yarn  may  be  left  with  more  size 
and  moisture  in  them  than  the  finer  counts.  The 
latter  should  be  well  squeezed  in  every  case. 

The  foregoing  remarks  apply  mainly  to  those 
yarns  which  are  "pure"  sized.  In  heavier  coloured 
sizing  the  warps  are  generally  treated  twice.  In 
the  first  operation  the  warp  is  run  through  a 
"mixing"  composed  of  flour  and  water  only.  It 
is  then  well  dried,  and  afterwards  run  through 
a  "mixing"  consisting  of  flour  and  water,  together 


406      The  Chemistry  and  Practice  of  Sizing. 

with  the  necessary  weighting,  softening,  and  anti- 
septic substances,  such  as  Epsom  salts,  tallow, 
chloride  of  magnesium,  and  chloride  of  zinc.  This 
matter  is  further  dealt  with  on  pages  414  and  415. 

In  heavy  grey  sizing  the  warps  may  be  treated 
sufficiently  in  one  operation  to  obtain  the  desired 
weight,  if  the  system  of  immersion,  as  showrn  on 
plate  xiv,  be  adopted.  In  this  case  the  warp  is 
passed  through  the  size  box  once,  and  afterwards 
pressed  in  the  squeezing  apparatus.  It  then  re- 
enters the  size  box,  through  which  it  is  passed  twice. 
By  this  arrangement  a  heavy  weight  of  size  com- 
bined with  a  good  firm  "feel"  can  be  obtained  by 
once  sizing. 

Delivery  Winch. — This  winch,  which  is  shown 
on  page  399,  is  used  for  the  purpose  of  taking  the 
warp  from  the  squeezing  rollers  and  leading  it 
into  the  box  or  truck  waiting  to  receive  it.  The 
winch  is  driven  a  little  faster  than  the  warp  is 
delivered  from  the  squeezing  rollers,  and  in  this  way 
a  fair  amount  of  "pull"  is  exerted. 

The  Drying  Machine. — The  drying  machine 
consists  of  a  number  of  cylinders  arranged  either 
vertically,  as  shown  on  page  408,  or  horizontally. 
These  cylinders  are  made  of  tinned  iron  or  of 
copper,  and  they  are  provided  with  suitable  buckets 
for  discharging  the  condensed  water.  Each 
cylinder  is  fitted  with  vacuum  valves. 

The  vertical  arrangement  of  the  cylinders  is  the 


Ball  Sizing — Drying  Machine.  407 


more  convenient  of  the  two  for  many  reasons.  In 
the  first  place  the  cylinders  can  be  more  easily 
inspected  when  required,  In  the  second  place 
the  warps  can  be  more  readily  got  at  in  case  of 
breakages.  In  the  third  place  the  cylinders  can  be 
readily  detached  for  repairs,  and  altogether  it  is  a 
more  convenient  arrangement  in  every  way. 

Many  firms,  however,  prefer  the  horizontal,  or 
group  arrangement,  as  they  claim  that  better  work 
can  be  performed  with  it,  and  the  warps  can  be  kept 
"mellower."  They  also  claim  that  there  is  less 
danger  of  forming  "slack  yarn," 

It  is  probable  that  in  most  cases  the  horizontal 
arrangement  has  been  selected  simply  because  the 
particular  building  is  better  adapted  for  it.  Cylinders 
arranged  vertically  require  a  lofty  room,  and  this 
is  not  always  convenient.  As  far  as  the  question  of 
"mellowness"  is  concerned  this  is  a  matter  for 
the  sizer  to  arrange  by  suitable  treatment  of  the 
warps. 

In  drying,  the  warps  are  passed  round  the 
cylinders  the  required  number  of  times,  or  "laps," 
and  for  this  purpose  a  guiding  "raddle"  is  provided. 
Two  or  four  warps  may  be  dried  at  the  same  time 
on  one  machine.  After  drying,  the  warps  are 
delivered  in  coils  into  sheets.  These  sheets  should 
be  laid  on  a  low  wrooden  platform  which  has  been 
covered  with  linoleum  or  a  good  oilcloth.  The 
smooth  surface  thus  presented  removes  any  danger 


Vertical  Drying  Machine. 
Messrs.  Jackson  &  Brother,  Wharf  Foundry,  Bolton. 


Ball  Sizing —  The  Drying  Machine.  409 


of  damage  to  the  warps  or  to  the  sheets  through 
coming  in  contact  with  splinters  from  the  surface 
of  the  platform. 

The  drying  machine  may  be  driven  either  by 
a  friction  arrangement  or  by  a  small  engine,  as 
shown  on  page  408,  or  by  means  of  an  electric 
motor,  so  that  the  speed  of  the  machine  may  be 
regulated  to  suit  the  class  of  work  being  done. 
The  machine  shown  in  the  illustration  is  driven 
by  an  expanding  pulley  on  the  same  shaft  as 
a  spur  pinion,  which  engages  into  a  wheel  on  the 
drying  cylinder.  The  object  of  this  expanding 
pulley  is  to  adjust  the  speed  of  the  drying  machine 
to  that  of  any  other  machine  with  which  it  works  in 
conjunction.  The  advantage  of  this  arrangement 
is  more  applicable  to  piece  goods  than  to  warps,  as 
the  speed  of  the  drying  machine  should  be  governed 
by  altering  the  speed  of  the  engine  itself. 

If  an  engine  be  used  for  driving  the  machine 
the  exhaust  steam  should  be  blown  into  the  drying 
cylinders.  The  engine  should  be  constructed  with 
two  cylinders  so  that  it  can  be  started  from  any 
position,  If  it  contains  only  one  cylinder  the  fly- 
wheel will  require  ''baring"  over  into  position  each 
time  the  engine  is  started. 

Balling  Machine.  —  In  addition  to  theapparatus 
already  described,  a  "balling"  machine  is  sometimes 
used.  This  machine,  an  illustration  of  which  is  shown 
on  page  410,  is  used  for  wrapping  the  sized  and 


4io      The  Chemistry  and  Practice  of  Sizing. 

dried  warp  into  a  ball,  in  which  form  it  is  much  more 
convenient  to  handle  and  pack  for  delivery  to  the 
customer.  The  balling  machine  is  used  chiefly  for 
"light"  sized  yarns.  It  has  a  tendency  to  "break" 
the  size  a  little,  so  that  it  is  advisable  not  to  use  it 
for  heavily  sized  yarns.    The  latter  should  be  allowed 


Balling  Machine. 


to  remain  in  "sheets,"  as  they  "mellow"  better  in 
this  state  than  if  they  were  made  into  a  ball. 

The  Sizing  Ingredients. 
The  ingredients  used  in  ball  sizing  are  very 
similar  to  those  used  in  tape  sizing,  excepting  that 


Ball  or  Warp  Sizing. 


411 


Epsom  salts  are  used  to  a  greater  extent.  It  is 
usual  to  keep  a  standard  mixture  of  flour  and  water. 
This  may  contain  three  pounds  of  flour  in  each 
gallon  of  the  mixture  for  coloured  work  and  li^ht 
grey  sizing,  whilst  for  "heavy"  sizing  the  proportions 
will  be  similar  to  those  given  on  page  277.  The 
flour  should  be  allowed  to  steep  or  ferment  for  at 
least  a  week,  in  order  to  separate  the  granules  of 
starch.  Where  it  is  intended  to  size  grey  yarns  only 
the  flour  may  be  " steeped"  with  chloride  of  zinc, 
as  previously  described  on  page  82  et  seq.  Chloride 
of  zinc,  however,  is  not  always  a  permissible  in- 
gredient, and  where  its  use  would  be  objectionable 
it  will  be  necessary  to  ferment  the  flour  in  order  to 
get  the  desired  smoothness. 

It  has  been  previously  stated  that  fermented 
flour  contains  acids.  This  would  be  objectionable 
when  sizing  yarns  dyed  with  colours  sensitive  to 
acids,  such  as  benzo  reds,  etc.  In  such  cases 
it  would  be  necessary  to  neutralise  the  acids 
with  soda  crystals,  commonly  known  as  washing 
soda.  This  substance  is  better  than  caustic  soda 
for  this  purpose,  as  a  slight  excess  would  not  be 
injurious  to  such  colours,  whereas  a  little  free 
caustic  alkali  might  be  injurious. 

Coloured  yarns  and  white  yarns  are  sized  either 
for  weaving  purposes  only  or  for  weight.  In 
"pure"  sizing  the  mixture  should  consist  of  flour,  or 
some  other  form  of  starch,  tallow,  or  some  other 


4 1 2      The  Chemistry  and  Practice  of  Sizing. 

fatty  or  waxy  softener,  and  water.  If  the  goods  have 
to  be  weighted,  Epsom  salts  should  be  used  for  this 
purpose,  along  with  the  chlorides  of  magnesium 
and  zinc.  China  clay  is  not  a  suitable  substance  to 
employ  for  weighting  coloured  yarns,  as  it  would 
affect  the  colours  and  give  the  yarns  a  "peppery'' 
appearance  unless  suitably  tinted.  This  is  due  to 
China  clay  being  an  insoluble  substance. 

After  a  suitable  "mixing"  has  been  made  in  the 
beck  for  the  class  of  yarn  about  to  be  sized  it  is 
run  into  the  size  box,  where  it  is  boiled  for  one  to 
one-and-a-half  hours.  This  amount  of  boiling  is 
necessary,  otherwise  the  yarn  will  stick  together 
after  sizing  and  drying,  and  would  be  difficult  to 
open  out,  in  the  after  process  of  beaming,  without 
damage. 

''Mixing"  for  Coloured  Yarns. 

A  typical  "mixing"  to  put  35  per  cent,  of 
size  on  coloured  yarn,  together  with  the  directions 
for  applying  it,  will  give  the  reader  a  clearer  idea  of 
the  methods  adopted  in  coloured  ball  sizing.  For 
coloured  work  this  weight  is  usually  obtained  by 
passing  through  the  machine  twice. 

First  Passage. — A  "mixing"  containing  i\  pounds 
of  flour  to  each  gallon  of  water  is  first  made  and 
boiled  for  1  to  hours.  The  warps  are  run  through 
this  and  afterwards  thoroughly  dried  on  the  drying 
cylinders. 


" Light  Mixing "  for  White  Yarns.  413 


Second  Passage. — To  every  150  gallons  of  the 
mixture  of  flour  and  water  the  following  ingredients 
should  be  added  : — 

Epsom  Salts    1  cwt. 

Tallow   ..,   20  pounds. 

Chloride  of  Zinc  at  1020  T.      ...     15  gallons. 

The  warps  are  passed  through  this  second 
"mixing,"  and  afterwards  dried.  This  time  it  is 
necessary  to  avoid  over-drying,  and  the  warps 
should  come  off  the  drying  cylinders  rather  damp. 
They  are  afterwards  allowed  to  lie  over-night  in 
sheets,  in  order  that  the  moisture  may  be  evenly 
absorbed  by  the  yarn,  and  thus  give  to  them  the 
desired  "mellow''  and  pliable  condition. 

"Light  Mixing"  for  White  Yarns. 

The  following  "mixing"  is  suitable  for  white 
yarns  which  require  to  be  sized  for  weaving  only. 

Farina   56  pounds. 

Paraffin  Wax  ...    2  to  6  pounds. 

Tallow    1  to  2  pounds. 

Water,  sufficient  to  make  when  boiled   100  gallons. 

N.B. — Where  a  firm  feel  is  required,  rice  or  maize 
starch  should  be  used  in  place  of  farina,  and  the 
mixing  well  boiled.  Farina  will  not  stand  too 
much  boiling. 

Half  the  required  quantity  of  water  should  first  be 
placed  in  the  size  box.  The  farina  should  then  be 
mixed  by  hand  in  a  suitable  vessel  with  another 
portion  of  cold  water.    This  is  best  performed  by 


414      The  Chemistry  and  Practice  of  Sizing. 

mixing  about  10  pounds  at  a  time,  and  as  soon  as  it 
is  thoroughly  mixed  it  should  be  poured  into  the 
size  box,  the  operation  being  continued  until  the 
whole  of  the  farina  has  been  incorporated.  The 
paraffin  wax  and  tallow  is  then  added,  and  the 
mixture  brought  to  the  boil.  The  boiling  should 
be  continued  for  \  to  1  hour. 

The  quantity  of  paraffin  wax  and  tallow  for  the 
foregoing  " mixing''  depends  upon  the  class  of  yarns 
undergoing  treatment.  For  the  finer  counts,  such 
as  40  s  and  upwards  it  will  be  advisable  to  use  the 
maximum  quantity  given  in  the  recipe,  whilst  for 
counts  such  as  26's  to  30's,  the  minimum  quantity 
may  be  used. 

N.B. — Counts  below  2o's  will  require  a  stronger 
"mixing"  than  the  one  given  for  weaving  only. 

It  will  be  as  well  to  mention  at  this  point  that 
flour  is  not  suitable  for  sizing  white  yarns  on 
account  of  its  creamy  tint. 

It  is  not  necessary  to  go  into  details  in  regard 
to  the  ingredients,  and  the  various  u  mixings" 
used  in  heavy  grey  sizing ;  nor  is  it  necessary  to 
further  describe  the  method  of  applying  the  size 
to  the  yarn.  Sufficient  has  been  said  to  give 
the  practical  reader  all  the  information  he  may 
require.  It  is  worthy  of  mention,  however,  that  in 
very  heavy  ball  sized  grey  yarns  it  is  customary 
to  use  a  far  greater  proportion  of  chloride  of  zinc 
and  a  less  proportion  of  chloride  of  magnesium 


Ball  or  Warp  Sizing. 


415 


than  is  used  in  tape  sizing.  In  some  cases  it  is 
customary  to  use  a  larger  proportion  of  tallow  also. 
The  writer,  in  the  course  of  his  practice  as  a 
consulting  chemist,  has  come  across  "mixings"  in 
which  chloride  of  magnesium  has  been  present  in 
very  small  quantities,  whilst  the  proportion  of  tallow 
has  been  nearly  double  the  amount  used  for  the 
same  percentage  of  size  in  tape  sizing.  The  object 
of  this  is  to  give  to  the  yarns  a  great  amount  of 
pliability,  and  to  give  to  the  cloth  a  peculiar  dry 
''leathery  feel"  when  woven  and  pressed. 

There  is  a  demand  in  certain  markets  for  a 
cloth  which  will  almost  stand  on  end  when  opened 
out,  *  and  this  condition  is  obtained  by  using  very 
little  chloride  of  magnesium  as  a  " softener."  In 
order  to  give  the  yarns  the  necessary  moisture  for 
good  weaving  it  is  customary  to  place  wet  fents 
on  the  weavers'  beams. 

When  the  cloth  is  afterwards  folded  and  pressed 
it  causes  the  laps  to  stick  slightly  together  when 
opened  out,  and  each  lap  will  almost  stand  upright. 
It  is  probably  due  to  this  custom  of  wetting  the 
yarn  on  the  weaver's  beam  that  such  an  excess  of 
chloride  of  zinc  has  come  to  be  used  in  heavy  ball 
sized  warps.  The  authors  are  aware  that  it  is 
customary  in  some  cases  to  damp  tape  sized  yarns 
in  a  manner  similar  to  that  described,  but  it  is  rarely 
done  to  the  same  extent  as  for  ball  sized  yarns.  If 
tape  sized  yarns  were  damped  to  the  same  extent, 


4 1 6       The  Chemistry  and  Practice  of  Sizing. 

mildew  would  develop  in  the  weaving  shed.  This 
is  because  chloride  of  zinc  is  rarely  used  in  the  mixing 
in  the  same  quantities  as  it  is  in  ball  sizing. 

THE  TINTING  OF  THE  WARPS 
IN  THE  PROCESS  OF  BALL  SIZING. 

The  tinting  of  yarn  has  already  been  dealt  with 
under  tape  sizing,  but  in  this  process  it  can  be 
carried  out  to  a  limited  extent  only. 

Ball  or  warp  sizing  lends  itself  to  tinting  to  a 
very  much  greater  extent,  and  in  recent  years  a 
considerable  development  has  taken  place.  The 
reason  why  the  process  cannot  be  adapted  success- 
fully in  tape  sizing  will  be  apparent  to  those  who 
have  read  the  description  of  tape  sizing  and  ball 
sizing.  It  has  been  shown  that  tape  sizing  can  only 
be  successfully  applied  to  very  long  lengths  of  yarn, 
whereas  much  smaller  lengths  of  yarn  can  be 
treated  economically  in  ball  sizing, 

The  process  of  tinting  is  not  applicable  to  hank 
sizing  for  a  different  reason.  Tinting  must  be 
carried  out  in  boiling  size  to  be  at  all  successful. 
In  hank  sizing  this  would  be  impossible. 

Tinting  is  carried  out  with  various  objects.  In 
the  first  place  it  is  necessary  to  "blue"  bleached 
yarns  in  order  to  produce  a  brighter  and  a  better 
white.  In  the  second  place  a  fairly  good  white  may 
be  obtained  by  blueing  unbleached  yarns  made  from 
good  clean  American  cotton.    This  is  known  as  an 


"Blueing"  Bleached  Warps.  417 


"imitation  bleached  yarn."  In  the  third  place 
tinting  is  carried  out  with  the  object  of  dyeing  the 
yarn  some  distinctive  colour  such  as  various  shades 
of  pink,  blue,  green,  heliotrope,  imitation  indigoe, 
imitation  linen  shades,  etc.,  through  the  medium  of 
the  size.  These  operations  are  being  carried  out 
with  a  great  measure  of  success  for  certain  classes 
of  cotton  goods  where  cheapness  in  production  is 
an  essential  condition. 

"  Blueing  "  Bleached  Warps. 

Bleached  warps  may  be  "  blued"  in  a  size  tinted 
with  any  shade  of  blue  desired.  The  dyes  most 
frequently  used  are  methyl  violet,  methylene  blue, 
victoria  blue,  benzo  sky  blue,  and  diamine  sky  blue. 

Bleached  warps  should  be  sized  with  a  "clear 
boiling"  starch  like  farina.  Wheaten  flour  is  not 
suitable  as  it  deadens  the  white.  A  good  farina 
should  be  used  for  this  purpose  as  low  grade  farinas 
have  a  tendency  to  form  ''soft  beams"  in  the 
weaving  shed. 

Bleached  two-fold  yarns  are  not  usually  sized 
and  the  operation  of  "blueing"  is  best  carried  out  in 
the  soap  bath. 

"Imitation"  Bleached  Yarns. 

At  the  present  time  there  is  a  considerable 
demand  for  yarns  for  cheap  goods  which  will  look 
white  when  woven  with  coloured  yarns.  These 

A2 


4 1 8      The  Chemistry  and  Practice  of  Sizing. 

yarns  have  taken  the  place  of  "half-bleached"  yarns. 
They  answer  the  purpose  equally  well  for  certain 
goods  and  they  can  be  produced  much  more  cheaply. 

So  long  as  these  "imitation"  bleached  yarns  are 
not  compared  with  bleached  yarns  they  look  fairly 
white  and  they  suit  the  coloured  stripes  and  checks 
for  which  they  are  intended. 

For  the  production  of  ''imitation  whites"  a  good 
clean  yarn  made  from  good  class  American  cotton 
should  be  employed. 

In  order  to  produce  a  bleached  effect  on  grey 
yarns  a  blue  of  a  reddish  tint  should  be  used.  The 
red  neutralises  the  yellow  tint  natural  to  American 
cotton,  whereas  a  "bluey"  blue  would  have  a 
tendency  to  produce  a  greenish  effect. 

In  order  to  get  the  best  results  it  is  necessary  to 
size  and  tint  twice.  The  double  boiling  and 
"blueing"  reduces  the  original  colour  of  the  yarn 
much  more  than  if  it  were  boiled  once  only.  In  the 
first  passage  only  half  the  depth  of  tone  should  be 
aimed  at.  Thus,  if  a  "lot'*  of  twenty  warps  are 
being  treated  they  should  be  run  through  the  tinted 
size  once,  then  reversed  and  run  through  a  second 
time.  The  second  run  gives  a  splendid  touch  to 
the  tone  and  the  result  is  altogether  superior  to 
that  which  is  obtained  if  the  full  tint  is  produced 
in  one  passage.  The  warp  should  not  be  ' 4  dried 
up"  between  the  first  and  second  run  unless  a 
''double"  size  is  required.     In  all  cases  it  is  better 


Tinting  Ball  Sized  Warps% 


419 


to  run  a  trial  lot  in  order  to  get  the  right  tint  before 
dealing  with  the  whole  of  the  warps. 

Tinting  Creams. 

Various  shades  of  cream  may  be  obtained  in 
the  sizing  operation.  Occasionally  the  tints  are 
produced  on  yarn  which  has  been  bleached  or  "half 
bleached,"  but  in  many  cases  they  are  obtained  on 
natural  grey  cotton.  Bleached  yarn  gives  a  much 
superior  effect,  but  for  certain  fabrics  the  former  is 
quite  good  enough.  The  principal  colours  employed 
in  producing  creams  are  chloramine  yellow,  chrys- 
amine  yellow,  chrysophenene  yellow,  benzo-chrome 
brown  G,  and  mikado  orange. 

Where  a  straw7  or  corn  shade  is  required  it  will 
be  necessary  to  use  the  brown  or  orange  dyes 
along  with  the  yellows,  according  to  the  tint 
required. 

Tinting  Pinks,  Rose  Shades,  etc. 

A  great  variety  of  pink  shades  can  be  obtained 
in  the  sizing  operation.  Either  bleached  or  "half 
bleached"  yarn,  or  natural  grey  yarn  may  be  used 
as  required.  The  most  useful  dyes  for  this  purpose 
are  erica  pink,  the  diamine  colours,  benzo  fast  red, 
various  shades  of  geranine  pink,  rhodamine,  rhoduline, 
magenta,  etc.  The  results  are  better  and  more 
even  if  a  second  run  be  given  as  described  under 
" imitation"  bleached  yarns. 


420      The  Chemistry  and  Practice  of  Sizing, 


Tinting  Sky  Blues,  etc. 

Many  light  blue  shades  can  be  obtained  by 
tinting  the  size.  Darker  shades  may  be  obtained 
by  passing  the  warp  a  second  time  through  the 
size,  which  should  be  kept  at  the  full  boil.  Light 
shades  of  blue  can  be  got  by  one  passage,  but  if 
evenness  of  colour  be  required  it  is  better  to 
use  a  weaker  dye  and  run  twice.  If  darker 
shades  are  required  it  will  be  necessary  to  run 
twice,  using  a  much  stronger  solution  of  dye.  In 
this  way  almost  any  depth  of  colour  may  be  obtained. 
If  the  warps  require  to  be  " twice"  sized  they  must 
be  " dried  up"  after  the  first  passage.  This  is  not 
necessary  if  "once"  sizing  be  sufficient. 

"  Topping"  Indigoes. 

It  is  a  common  practice  to  "top"  indigo  dyed 
warps  where  the  yarn  is  required  for  very  cheap 
classes  of  cloth.  The  "topping"  is  performed  in  the 
sizing  operation  as  follows  : — 

The  warps  are  first  dyed  a  light  indigo,  after 
which  they  are  run  through  a  size  tinted  with 
methylene  blue,  bismarck  brown,  and  magenta. 
The  brown  and  magenta  dyes  give  body  to  the 
methylene  blue,  and,  at  the  same  time,  impart  the 
red  tint  natural  to  indigo.  If  very  dark  shades  are 
required  it  will  be  necessary  to  use  a  certain 
proportion  of  black  dye,     Some  surprising  results 


Tinting  Ball  Sized  Warps. 


can  be  obtained  in  "topping"  indigo  dyed  yarn 
if  suitable  colours  be  used  in  the  size. 

Tinting  Heliotropes. 

Many  shades  of  heliotrope  can  be  obtained  by 
tinting  the  size.  Various  shades  of  violet,  blue, 
and  magenta  are  used  for  this  purpose.  The 
principal  dyes  which  may  be  employed  are  diamine 
violet  N,  oxydiamine  violet  R,  direct  blues,  and 
various  shades  of  magenta.  Direct  heliotropes  are 
now  being  manufactured  and  employed  in  tinting 
to  a  considerable  extent. 

Tinting  Sage  Greens. 

Many  shades  of  sage  green  can  be  obtained  in 
the  size  box.  For  this  purpose  mixtures  of  yellow, 
orange,  and  blue  dyes  should  be  used.  From 
these  colours  almost  any  shade  of  sage  green  can 
be  obtained. 

There  are  also  many  new  direct  green  and  sage 
green  dyes  on  the  market  at  the  present  time,  and 
with  them  a  great  variety  of  work  can  be  carried 
out  in  the  size  box  which  formerly  could  only  be 
done  by  dyeing. 

Tinting  Linen  Shades  on  Cotton. 

There  is  a  considerable  business  done  in  cotton 
yarns  tinted  to  imitate  linen  yarns.  They  are 
employed  in  the  manufacture  of  certain  cloths  such 


422       The  Chemistry  and  Practice  of  Sizing. 


as  imitation  linen  dress  goods,  etc.  The  object  is  to 
obtain  the  shade  of  unbleached  linen.  Linen 
shades  may  be  obtained  by  the  use  of  mixtures 
of  various  shades  of  brown  with  direct  black.  The 
black  dye  is  used  to  deaden  the  effect  of  the 
brown.  The  principal  brown  dyes  employed  for 
this  class  of  tinting  are  cotton  brown  A,  cotton 
brown  N,  diamine  brown  3G,  catechine  brown  3G, 
pluto  brown,  benzo-chrome  brown  G,  benzo  brown 
G,  diamine  nitrazol  brown  BD,  diamine  nitrazol 
brown  RD,  direct  brown  GG.  The  particular 
shade  of  brown  depends  upon  whether  a  yellowish 
or  reddish  tint  be  required. 


WARP  BLEACHING. 

Warp  bleaching  and  dyeing  are  essential  parts 
of  the  warp  sizers  business.  Warp  dyeing  is 
beyond  the  scope  of  a  work  devoted  to  sizing  but 
the  bleaching  of  warps  may  be  dealt  with. 

For  pure  zvhites  it  is  necessary  to  subject  the 
warps  to  a  full  bleach,  and  they  should  be  kier 
boiled.  This  process  is  also  essential  for  certain 
very  delicate  shades  of  dyed  yarn  where  special 
brightness  and  bloom  are  required  in  self-coloured 
plain  goods,  in  which  the  weft  and  warp  have  to  be  the 
same  shade  of  colour.  Most  light  shades,  however, 
may  be  successfully  dyed  on  "machine  bleached"  or 
on  "half  bleached"  yarns,  and  medium  shades  may  be 


Warp  Bleaching. 


423 


dyed  on  yarn  which  has  been  " scoured"  only,  i.e., 
ash  boiled  and  "soured  "on  the  machine.  As  a  general 
rule  it  is  unnecessary  to  kier  boil  for  dyeing  purposes 
except  for  special  requirements,  such  as  previously 
mentioned,  where  perfect  evenness  of  shade  has  to 
be  obtained.  "Machine  boiling"  and  bleaching  is 
quite  sufficient  for  most  classes  of  dyed  yarns  and 
also  for  certain  "  whites"  which  are  required  for 
stripes  and  checks.  At  the  same  time  it  is  necessary 
to  point  out  that  it  is  only  possible  to  soften  and 
remove  the  objectionable  ticks  and  motes  found  in 
cotton  yarn  by  kier  boiling,  and  where  they  would  be 
objectionable  kier  boiling  must  be  resorted  to. 

Kier  boiling  is  necessary  for  pure  whites  and 
for  very  delicate  shades  of  dyes  for  other  reasons. 
In  the  first  place,  unless  the  yarn  be  thoroughly 
"bottomed"  there  is  always  a  tendency  for  the 
natural  colour  of  the  cotton  to  strike  through  the 
dye  and  spoil  the  tint.  This  is  also  the  case  where 
pure  whites  are  required.  It  is  a  common  thing  to 
find  white  cloth  discoloured  after  it  has  been  stored 
for  some  time  if  the  yarn  has  not  been  sufficiently 
boiled.  It  will  be  advisable,  therefore,  to  deal 
with  warp  bleaching  in  two  sections,  viz. : — "  kier 
boiling  "  and  "machine  boiling," 

THE  KIER  BOILING  PROCESS. 

In  this  process  the  warps  are  first  passed  into  a 
three-box  "wetting  out"  or  boiling  machine,  where 


424      The  Chemistry  and  Practice  of  Sizing. 

they  are  boiled  with  soda  ash  in  the  first  two  boxes 
and  washed  in  the  third.  From  the  " wetting  out" 
machine  they  are  carried  by  means  of  a  winch  into 
the  first  kier,  which  may  be  either  a  high  pressure 
kieroranopen  kier  according  to  the  bleaching,  or  to 
the  convenience  of  the  bleacher.  Each  class  of 
kier  has  its  advantages  and  disadvantages  and 
these  will  be  discussed  later.  The  warps  should 
be  plaited  in  long  even  layers  by  boys  standing 
in  the  kier.  These  boys  should  be  shod  with 
clogs  without  iron  soles  and  the  soles  should  be 
attached  to  the  uppers  with  copper  nails.  If  iron 
comes  in  contact  with  the  warp  it  will  become  iron- 
stained  and  this  is  a  very  serious  matter  when 
dealing  with  warp  bleaching. 

The  warps  should  be  boiled  with  soda  ash  and 
caustic  soda  for  eight  hours  in  the  pressure  kier,  using 
1  per  cent,  of  dry  soda  ash  and  1  per  cent,  of  caustic 
soda  solution  at  70°  Tw.  to  the  weight  of  cotton 
treated.  If  the  open  kier  be  used  the  boiling  should 
be  continued  for  1  2  hours,  using  the  same  proportions 
of  soda  ash  and  caustic  soda. 

After  boiling,  the  warps  are  led  into  a  four-box 
washing  machine  which  is  arranged  as  follows  : — The 
first  box  is  used  for  washing,  the  second  for 
"souring"  with  acid,  at  1  to  \\°  Tw.,  and  the  third  and 
fourth  for  washing.  From  this  machine  the  warps 
are  led  into  the  second  kier  and  again  boiled  with 
soda  ash  and  caustic  soda,  using  half  the  quantity  of 


Warp  Bleaching — "Kiev  Boiling!'  425 

soda  ash  and  caustic  soda  employed  in  the  first 
operation.  This  time  the  boiling  should  not  exceed 
four  hours  in  the  pressure  kier  and  six  hours  in 
the  open  kier. 

After  the  second  boiling  the  warps  are  led  back 
to  the  machine  where  they  are  again  washed  in 
water.  From  here  they  are  led  to  the  chemic 
cisterns  where  they  are  plaited  dowrn  by  boys. 
The  chemic  liquor  is  then  pumped  up  from  a  well 
or  reserve  tank  underneath  the  cistern  and  sprayed 
over  the  yarn.  This  operation  is  continued  for  four 
hours.  The  chemic  liquor  should  be  used  at  about 
I  to  i°  Tw.  After  chemicking,  the  warps  are 
led  back  to  the  four-box  washing  machine  where 
they  are  washed  in  the  first  box,  "soured''  in  the 
second,  and  washed  in  the  third  and  fourth. 
From  this  machine  they  are  led  to  another  four 
box  machine  where  they  are  run  through  water 
in  the  first  box,  boiling  soap  and  water  in  the 
second  and  third,  and  water  in  the  fourth,  after 
which  they  are  carried  to  the  drying  machine.  If 
the  warps  are  for  " twice"  sizing  they  may  be 
given  the  first  passage  through  the  size  in  the 
condition  they  come  from  the  nip  of  the  washing 
and  soaping  machine,  but  if  they  have  to  be 
"once"  sized  only  they  will  require  to  be  dried 
first.  Two-fold  yarns  intended  for  "  whites  "may 
be  "  blued"  in  the  soaping  process  as  previously 
mentioned. 


426       The  Chemistry  and  Practice  of  Sizing. 


Such  briefly  are  the  operations  involved  in 
kier  boiling.  Certain  important  details  not  mentioned 
in  this  description  may  now  be  dealt  with  more 
fully. 

Where  the  warps  are  boiled  under  pressure  great 
care  must  be  taken  that  they  are  thoroughly  "wet 
out"  before  they  enter  the  kier  otherwise  damage 
is  almost  certain  to  occur  during  the  boiling  process. 

The  object  of  "wetting  out"  is  to  discharge  all 
traces  of  air  in  the  cotton.  Unless  this  precaution 
be  taken  the  oxygen  will,  in  the  presence  of  caustic 
alkalies  at  high  temperatures,  act  on  the  cellulose, 
and  form  oxycellulose,  and  the  yarns  will  be  tendered 
wherever  this  occurs. 

If  the  warps  are  boiled  in  an  open  kier  there 
is  less  danger  of  damage  from  the  production  of 
oxycellulose,  but  the  process  takes  longer  and  the 
motes  and  ticks  are  not  so  easily  softened  and 
removed. 

Care  must  also  be  exercised  that  all  the  air  is 
driven  out  of  the  kier  before  it  is  finally  closed 
down,  and,  in  order  to  effect  this,  the  "air  cock" 
should  be  left  open  at  the  commencement  of  the 
boiling  until  it  is  judged  that  the  air  has  been  entirely 
driven  out  with  the  escaping  steam.  The  "air  cock" 
should  be  left  slightly  open  during  the  whole  of  the 
boiling  process.  No  danger  need  be  feared  in 
pressure  kier  boiling  if  the  process  is  carried  out 
properly,  and  if  the  right  type  of  kier  be  employed. 


Warp  Bleaching — High  Pressure  Kier.  427 

The  best  form  of  high  pressure  kier  for  boiling 
warps  is  shown  on  page  428.  This  kier  has  come 
into  high  favour  since  the  introduction  of  the  caustic 
soda  process  of  bleaching.  It  is  fitted  with  a  heater 
and  centrifugal  pump  as  shown  in  the  illustration. 
Many  advantages  can  be  claimed  for  it  over  the  old 
type  of  high  pressure  kier.  In  the  first  place,  no  live 
steam  enters  the  kier,  and  therefore  no  dirt  can 
be  carried  over  from  the  boiler  to  stain  the  warps. 
In  the  second  place,  the  liquor  used  for  boiling 
is  not  diluted  by  the  steam  and  so  remains  constant  as 
far  as  strength  is  concerned.  In  the  third  place, 
perfect  circulation  is  maintained,  and  lastly,  less  steam 
is  required  to  maintain  the  temperature  in  the  kier. 

The  following  description  of  the  method  of 
working  the  kier  will  more  fully  explain  its 
construction : — 

After  the  kier  has  been  charged  with  the  warps 
to  be  treated,  the  liquor,  which  consists  of  a  solution 
of  soda  ash  and  caustic  soda  previously  mixed 
in  a  cistern  arranged  for  this  purpose,  is  admitted 
at  the  connection  at  the  bottom  of  the  kier,  where 
it  passes  through  the  underside  of  the  grid.  This 
is  accomplished  by  first  opening  the  liquor  valve 
and  the  air  cock  and  closing  the  circulating  valves 
and  the  outlet  valves. 

By  feeding  the  liquor  from  the  bottom  of  the 
kier  upwards  the  warps  are  prevented  from  being 
compressed  or  packed,  and  this  allows  the  liquor  to 


428      The  Chemistry  and.  Practice  of  Sizing. 

circulate  freely  through  every  portion  of  the  yarn 
thus  ensuring  even  treatment.     Another  advantage 


Walsh  Type  of  High  Pressure  Kier,  showing  Tubular  Heater, 
Pump  and  Circulating  Pipes,  etc. 
Messrs.  Jackson  &  Brother,  Wharf  Foundry,  Bolton. 

obtained  by  forcing  the  liquor  upwards  is  that  the 
air  is  more  easily  driven  out  of  the  kier. 


Machine  Boiling  and  Bleaching. 


429 


When  the  kier  has  been  charged  with  sufficient 
liquor,  as  indicated  by  the  gauge,  to  cover  the 
warps  to  a  depth  of  about  12  inches,  the  supply  is 
shut  off  by  closing  the  valves.  The  liquor  is 
circulated  through  the  heater  by  means  of  a  cen- 
trifugal pump. 

A  simple  form  of  indicator  shows  how  the  liquor 
is  circulating. 

After  the  warps  have  been  sufficiently  boiled  the 
pressure  in  the  kier  is  let  down  by  shutting  off  the 
steam  from  the  heater.  Clean  water,  preferably 
hot,  is  forced  through  the  heater  into  the  kier,  in 
order  to  wash  out  as  much  of  the  alkali  as  possible. 

All  types  of  kiers  should  be  thoroughly  lime- 
washed  previous  to  use,  and  this  lime-washing  should 
be  repeated  every  few  weeks,  or  whenever  required. 
Care  must  be  exercised  by  the  bleacher  that  no  part 
of  the  kier  is  left  unprotected,  otherwise  iron  stains 
are  sure  to  occur.  These  stains  are  very  objectionable 
in  warp  bleaching,  as  they  have  a  tendency  to  tender 
the  yarn,  and  they  are  not  so  easily  removed  as  in 
piece  goods. 

MACHINE  BOILING  AND  BLEACHING. 

As  previously  stated,  it  is  not  always  necessary 
to  subject  the  warps  to  kier  boiling  and  for  many 
purposes  the  boiling  and  bleaching  can  be  carried 
out  in  a  perfectly  satisfactory  manner  on  the  machine. 
The  writer  does  not  recommend  machine  bleaching 


430      The  Chemistry  and  Practice  of  Sizing. 

for  warps  which  have  to  be  pure  white  or  for  those 
which  have  to  be  dyed  the  most  delicate  shades  for 
plain  self-coloured  goods  for  the  reasons  already 
given  on  page  423.  Good  results,  however,  may  be 
obtained  in  the  production  of  "whites"  for  stripes  and 
fancy  designs,  and  in  the  production  of  "bleached 
bottoms"  intended  for  dyeing  many  pale  shades,  such 
as  pinks,  creams,  blues,  heliotropes,  canary  tints, 
etc.  As  a  matter  of  fact  many  of  these  colours 
are  dyed  on  warps  which  have  been  "scoured"  only, 
but  there  is  no  comparison  with  the  results 
obtained  on  bleached  yarn.  Bleached  yarn  gives  a 
brightness  and  clearness  of  tint  altogether  different 
from  that  which  is  produced  on  unbleached  cotton. 

One  disadvantage  of  this  process  is  that  the 
ticks  and  motes  are  not  softened  or  removed  to 
anything  like  the  extent  as  they  are  in  kier 
boiling. 

In  machine  boiling  and  bleaching  the  warps  are 
led  into  the  boiling  machine  which  should  be 
constructed  with  at  least  four  boxes,  In  the 
first  three  boxes  they  are  boiled  with  soda  ash 
and  caustic  soda,  and  washed  with  water  in  the 
fourth.  Two  to  four  pounds  of  soda  ash  and  the 
same  quantity  of  caustic  soda,  at  70°  T,  should 
be  added  to  the  water  in  each  box,  and  the 
liquor  should  be  "strengthened  up"  as  the  work 
proceeds.  This  is  left  to  the  judgment  of  the 
bleacher  who  can  tell  by  experience,  and  by  the 


Boiling  and  Washing  Machines. 


43i 


appearance  of  the  yarn,  when  the  addition  of  fresh 
soda  ash  and  caustic  soda  is  required. 

After  the  warps  have  passed  through  the  first 
machine,  as  herewith  described,  they  are  led  to  a 
second  four-box  machine,  each  box  of  which  is 
charged  with  "chemic"  or  bleaching  liquor.  The 
warps  are  passed  through  this  liquor  and  after- 
wards led  into  boxes  where  they  are  allowed  to  "air" 
for  some  time.  They  are  then  run  through  a  six 
or  eight  box  machine  where  they  are  treated  as 
follows  : — In  the  first  and  second  boxes  they  are 
washed,  in  the  third  " soured"  in  acid,  in  the  fourth 
and  fifth  washed,  and  in  the  sixth  soaped.  If  the 
warps  do  not  require  soaping  the  last  box  should  be 
used  for  washing. 

Before  leaving  this  portion  of  the  subject  it  may 
be  as  well  to  mention  that  it  is  customary  in  many 
places  to  run  the  warps  through  warm  "chemic," 
and  it  is  also  customary  to  use  the  acid  ''sours"  warm. 
Whether  this  is  advisable  is  a  matter  on  which 
there  are  many  different  opinions.  There  is 
certainly  a  danger  of  producing  tendered  warps 
unless  the  "chemic"  be  used  with  a  great  deal  of 
care  and  discretion.  At  the  same  time  it  must  be 
admitted  that  the  process  is  carried  on  regularly 
without  complaints  of  damage  occurring.  It  must 
be  taken  into  consideration  that  the  passage  of 
the  warps  through  the  bleaching  liquor  is  rapid, 
and  that  they  soon  cool  down.     The  object  of 


432      The  Chemistry  and  Practice  of  Sizing. 

using  warm  acid  for  " souring"  is  to  remove  more 
quickly  the  stains  which  may  occur  through 
insufficient  boiling  and  washing, 

"BOILING"  AND  WASHING  MACHINES, 

The  boiling  and  washing  machines  are  usually 
constructed  of  pitch-pine.  They  are  driven  by 
means  of  a  shaft  arranged  along  the  back  of  the 
machines.  This  shaft  should  be  "set"  perfectly 
level.  The  driving  gear  is  arranged  with  a  counter- 
shaft  and  fast  and  loose  pulleys.  The  speed  of  the 
pulleys  should  be  from  150  to  200  revolutions  per 
minute.  The  best  arrangement  for  driving  is  by 
means  of  a  pinion  and  a  spur  wheel. 

The  machines  may  contain  four  or  more  boxes, 
according  to  the  work  to  be  carried  out.  Each  box 
is  usually  30  inches  wide,  30  inches  deep  and  66 
inches  long.  They  are  fitted  with  a  pair  of  squeez- 
ing rollers,  immersion  rollers,  "throw-out"  gear, 
boil  pipes,  "let-off"  pipe,  and  delivery  winch. 

Squeezing  Rollers. — These  rollers  are  placed 
over  the  partitions  of  the  boxes  level  and  square 
with  the  driving  shaft. 

The  bottom  roller,  which  is  driven,  should  be 
from  11  to  12  inches  in  diameter  and  care  should  be 
taken  that  all  the  bottom  rollers  on  the  machine  are 
of  the  same  diameter,  otherwise  they  may  damage 
the  yarn  by  causing  too  much  drag  on  it.  These 
rollers  should  be  very   carefully  wrapped  with  a 


*  *  Warp  Bleaching 1 9 — Immersion  Rollers.  433 

"hessian  lapping''  and  any  slight  increase  in  the 
diameter  of  successive  rollers  on  any  one  machine 
(which  may  be  required  for  the  purpose  of  exerting 
a  slight  pull),  should  be  got  by  slightly  increasing  the 
"lapping."  It  is  only  possible  to  get  the  exact 
amount  of  "lapping"  for  each  roller  of  the  machine 
for  correct  working  by  a  practical  test  under  working 
conditions. 

The  top  roller  should  be  10  to  11  inches  in 
diameter,  and  it  should  be  "lapped"  with  two  or 
three  rounds  of  "hessian." 

The  squeezing  rollers  should  run  at  33  revolutions 
per  minute  and  the  speed  of  the  machine  should  then 
give  2,000  yards  per  hour. 

Immersion  Rollers. — These  rollers  may  be  made 
either  of  copper,  brass,  iron  or  wood,  according  to  the 
purpose  for  which  the  machine  is  employed.  Usually 
there  are  four  top  and  five  bottom  rollers  in  each  box. 
They  must  be  "set"  perfectly  level,  and  also  parallel 
with  the  squeezing  rollers,  otherwise  the  warps  will 
not  run  true.  This  will  be  quickly  discovered 
when  the  machine  is  set  to  work.  The  rollers 
should  be  fitted  to  turn  easily  whilst  hot.  A 
"sticking"  roller  is  a  common  cause  of  damage 
to  the  warps,  and  it  is  not  unusual  to  find  the 
rollers  working  "tight"  in  new  machines.  This 
is  due  to  the  makers  not  allowing  for  the 
expansion  which  takes  place  when  they  are  heated. 
The  rollers  may  run  easily  enough  whilst  cold, 

B2 


434      The  Chemistry  and  Practice  of  Sizing. 

but  they  stick  as  soon  as  the  temperature  is 
raised. 

Iron  rollers  may  be  employed  for  boiling  with 
soda  ash  and  caustic  soda,  and  for  ordinary  washing 
purposes.  For  "chemic"  it  is  better  to  use  wooden 
rollers,  whilst  for  the  acid  used  in  "souring,"  brass, 
copper,  or  wooden  rollers  may  be  used. 

"  Throw-Out  Gear." — The  machine  should  be 
fitted  with  a  " throw-out "  gear  running  the  full 
length  of  the  front  of  the  machine.  A  "dog  leg" 
crank  is  connected  with  the  " throw-out"  rod  and 
each  box  should  be  fitted  with  "throw-out"  handles. 
Those  who  have  to  work  the  machines  will 
appreciate  the  advantages  of  this  arrangement.  If 
the  "throw-out"  gear  is  arranged  with  a  fast  counter- 
shaft a  smaller  belt  will  be  required  and  the  machine 
throws  out  quicker. 

The  Boil  Pipes. — The  boil  pipes  are  perforated, 
and  they  may  be  made  either  of  copper  or  iron, 
according  to  requirements.  Iron  pipes  may  be 
used  for  soda  ash  and  caustic  soda  boiling. 

"Overflow "or  "Let-off"  Pipes. — ''Overflow" 
pipes  should  be  fitted  on  the  inside  of  the  boxes 
where  possible,  and  arranged  just  clear  of  the  top 
roller.  These  pipes  should  be  fitted  with  a  swivel 
so  that  the  liquor  can  be  run  off  from  any  height. 
Sometimes  the  "overflow"  pipes  are  fitted  on  the 
outside  of  the  boxes.  The  objection  to  this  arrange- 
ment is  that  it  causes  a  great  amount  of  splashing 


"Warp  Bleaching' — "Overflow"  Pipes.  435 

when  the  liquor  is  flowing,  whereas  if  the  " overflow'' 
pipe  is  inside  the  box  the  liquor  runs  direct  into 
the  drain. 

A  combined  "let-off"  and  "overflow"  pipe  can 
be  arranged  by  fitting  an  iron  collar  on  the  "over- 
flow" pipe  two  or  three  inches  from  the  bottom. 
When  the  pipe  is  placed  in  position  the  collar  fits 
over  and  completely  closes  the  plug  hole  at  the 
bottom  of  the  box.  When  it  is  desired  to  empty 
the  box  the  pipe  is  lifted  out  and  the  liquor  flows 
into  the  drain. 

The  Delivery  Winch. — The  delivery  winch 
should  be  double  the  width  of  the  box  in  order 
to  allow  for  the  opening  out  of  the  warps. 
Engineers  are  inclined  to  make  these  winches  on 
the  small  side  but  they  are  not  so  convenient  as  the 
wider  ones. 


436      The  Chemistry  and  Practice  of  Sizing. 


CHAPTER  X. 

Hank  Sizing  and  Bleaching. 


HANK  sizing  is  employed  almost  entirely  for 
coloured  and  bleached  yarns,  and  for  grey 
yarns  which  are  intended  to  be  used  in  fancy 
coloured  woven  goods.  This  method  is  employed 
in  sizing  weft. 

It  is  sometimes  suggested  that  hank  sizing  is  an 
obsolete  method  of  incorporating  size  with  the  warp, 
but  for  certain  classes  of  coloured  woven  goods  it  is 
still  the  best  method  to  employ.  For  one  reason 
the  preparatory  machinery  used  by  many  manu- 
facturers of  fancy  coloured  woven  goods  is  adapted 
for  treating  yarns  in  the  hank.  There  are  also 
special  cases  where  it  is  more  advantageous  to  size 
in  the  hank  than  in  the  warp.  For  instance,  some 
manufacturers  bleach,  dye,  and  size  their  own  yarn, 
In  such  cases  the  manufacturer  is  able  to  keep  a 
smaller  stock  of  miscellaneous  lots  of  dyed  and  sized 
yarns  of  various  counts  in  the  hank.  This  enables 
him  to  make  a  warp  of  any  length  at  a  very  short 


"Hank  Sizing" 


437 


notice,  especially  where  the  pattern  in  the  cloth 
requires  a  few  ends  only  of  certain  colours. 

There  are  some  firms  who  not  only  bleach,  dye, 
and  size  their  yarns,  but  who  finish  the  woven  cloth 
for  the  market  also.  In  such  cases  an  endeavour  is 
made,  for  obvious  reasons,  to  keep  the  trade  confined 
to  as  small  a  range  of  colours  as  possible.  This  is 
only  possible  to  manufacturers  of  specialities.  It 
rarely  happens  that  there  are  more  than  seven  or 
eight  colours  in  one  pattern,  and  this  number  is 
exceptional.  As  a  rule  there  are  not  more  than 
three  or  four  colours.  With  these,  together  with 
the  white  and  grey  yarn,  combinations  can  be 
obtained  from  wThich  a  great  variety  of  patterns  may 
be  produced.  Such  firms  as  the  above  are  exceptions, 
and  as  a  general  rule  hank  sizing,  like  ball  sizing, 
is  performed  by  the  public  dyer,  to  whom  the 
manufacturer  sends  the  grey  yarns.  The  dyer 
has  to  lay  himself  out  for  the  requirements  of  his 
different  customers,  and  consequently  he  must  be 
prepared  to  treat  a  very  much  greater  range  of 
coloured  yarns  than  the  manufacturer  who  dyes 
and  sizes  for  his  own  trade. 

In  hank  sizing  it  is  customary  to  size  the  yarn 
at  least  twice,  and  in  some  cases  three  times.  In  the 
first  operation  an  endeavour  is  made  to  incorporate 
as  much  size  as  possible  with  the  yarn.  For  this 
purpose  the  size  is  always  made  stronger  for  the 
first  operation  than  for  the  second  and  third. 


438      The  Chemistry  and  Practice  of  Sizing. 

In  sizing  grey  yarns  it  is  necessary  to  boil  the 
hanks  in  water  for  several  hours  otherwise  it  would 
be  impossible  to  size  them  successfully.  The 
boiling  operation  removes  the  waxy  and  oily 
matters  from  the  cotton  to  a  great  extent,  and  so 
allows  the  size  to  penetrate  the  threads.  Sometimes 
the  grey  yarn  is  boiled  in  a  3  per  cent,  solution  of 
washing  soda  instead  of  in  water  only.  After 
boiling,  the  hanks  are  placed  in  the  hydro-extractor, 
an  illustration  of  which  is  shown  on  page  452. 

Coloured  yarns  are  taken  straight  from  the  dye 
house  and  well  treated  in  the  hydro-extractor, 
after  which  they  are  sized.  It  is  unnecessary  to 
boil  coloured  yams  in  water  previous  to  sizing  as  the 
operations  involved  in  scouring  and  dyeing  render 
them  fit  to  take  the  size  without  further  treatment. 
Bleached  yarns  are  treated  in  a  similar  manner 
to  coloured  yarns. 

Hank  sizing  is  essentially  a  light  sizing  process, 
and,  as  a  matter  of  fact,  it  is  considered  very  heavy 
if  10  to  15  per  cent,  of  size  is  incorporated  with  the 
yarn. 

HANK  SIZING  PLANT. 

A  great  many  improvements  have  been  made 
in  the  apparatus  employed  for  hank  sizing  in  recent 
years,  and  the  old  slow  process  of  sizing  by  hand 
has  nearly  passed  away. 


uHank  Sizing'  Machine.  439 


The  machine  used  for  hank  sizing  consists  of  a 
size  box,  in  which  are  fitted  two  copper  winches, 


and  two  hooks.  The  winches,  which  are  constructed 
in  hexagonal  form  so  as  to  get  a  better  grip  on  the 


44-0      The  Chemistry  and  Practice  of  Sizing. 

yarn  whilst  revolving,  are  used  for  immersing  the 
hanks  of  yarn  in  the  size,  and  the  hooks,  which  are 
made  of  steel,  are  used  for  mechanically  wringing 
the  hank  after  it  has  been  sized.  One  of  the  hooks 
is  fixed,  whilst  the  other  is  arranged  to  revolve 
three  turns. 

An  illustration  of  one  of  the  best  known 
hank  sizing  machines  is  shown  on  page  439. 
Another  machine  is  illustrated  on  page  441.  This 
is  a  double  machine,  and  can  be  employed  with 
advantage  in  many  cases,  as  it  allows  two  operatives 
to  work  at  the  same  time.  With  this  arrangement 
double  the  output  can  be  obtained  from  the  same 
mechanism  for  driving  as  from  a  single  machine, 
and  the  employer  is  able  to  get  work  performed  by 
one  machine  which  would  require  two  single 
machines  with  double  the  mechanism. 

Method  of  Applying  the  Size. 

The  method  of  applying  the  size  is  as  follows: — 
On  receiving  the  yarn,  the  sizer  proceeds  to  "head" 
it  off  in  i^-pound  bunches  or  "noddles"  (it  is  under- 
stood that  the  yarn  has  been  already  banded, 
previous  to  drying,  etc.,  with  a  small  band  round 
every  half-pound).  He  then  takes  20  pounds  of 
yarn  and  dips  it  into  the  size.  After  it  has  been 
immersed  it  is  placed  on  a  ledge  constructed  for  the 
purpose  in  the  size  box.  He  then  takes  one  bunch 
and  places  it  on  one  of  the  revolving  winches  which 


442       The  Chemistry  and  Practice  of  Sizing, 

immerses  it  in  the  size.  As  soon  as  the  first  bunch 
is  on  the  winch  he  places  a  second  bunch  on  the 
other  winch.  These  are  allowed  to  run  tor  a  few 
moments.  The  first  bunch  of  yarn  is  then  taken 
off  and  placed  on  the  wringing  hooks.  One  of  the 
hooks  is  regulated  by  a  pin  so  that  the  yarn  may  be 
wrung  more  or  less  tightly  as  may  be  required. 

After  wringing,  the  "sizer"  runs  his  hand  down 
the  twisted  yarn  to  remove  the  superfluous  size. 
Whilst  the  wringing  is  taking  place  another  bunch 
of  yarn  is  put  on  the  vacant  winch,  which  is 
passed  through  the  size  as  before.  After  wringing, 
the  hook  will  take  one  turn  back.  This  allows  the 
"sizer"  to  take  the  yarn  off  the  hooks,  but  does  not 
entirely  untwist  it,  because  it  is  arranged  to  give 
three  turns  of  the  hook  in  wringing,  and  the  machine 
stops  automatically  at  one  turn  back.  In  this 
condition  the  yarn  is  easier  to  handle,  and  it  is 
easier  to  find  the  middle  when  it  comes  to  be 
shaken  out. 

The  sizing  machine  is  usually  run  at  the  speed 
of  four  "wringers"  per  minute. 

Method  of  Mixing  the  Size. 

The  "mixings"  used  in  hank  sizing  generally 
consist  of  flour,  tallow  and  water.  The  flour 
should  be  a  good  pure  wheaten  flour,  and  all 
mixtures  containing  rice  and  maize  flours  should  be 
strictly  avoided. 


"Hank  Sizing." 


443 


It  is  not  customary  to  steep  or  ferment  the  flour 
in  hank  sizing  to  the  same  extent  as  in  ball  and  tape 
sizing.  The  general  procedure  is  to  mix  sufficient 
for  one  or  two  days  supply  only.  This  is  not  an 
advisable  method  of  treating  the  flour,  as  there  is  a 
danger  of  fermentation  taking  place  on  the  yarn 
during  the  drying  operation  if  the  stove  be  a  slow 
one,  and  not  well  ventilated.  This  would  give  rise 
to  "soft"  places. 

It  would  be  advisable  in  all  cases  to  keep 
two  becks  for  the  flour,  one  beck  for  fermenting, 
and  the  other  as  a  store  beck  from  which  the  flour 
should  be  used.  The  flour  is  steeped  in  the 
proportion  of  i  pound  to  i  gallon  of  water.  When 
a  "mixing  "  is  made,  20  gallons  of  the  flour  in  steep 
should  be  run  into  a  "mixing"  beck,  or  tub,  and  20 
gallons  of  water  added. 

The  "mixing,"  which  is  used  at  about  110 
degrees  Fah.,  or  just  sufficiently  cool  for  the 
operative  to  handle  in  the  machine,  should  be  well 
boiled  previous  to  being  used. 

The  sizer  then  runs  into  the  machine  say  5  to  10 
gallons  of  boiled  size,  and  10  gallons  of  cold  water, 
according  to  the  "counts"  of  yarn.  Through  this 
mixture  20  pounds  of  yarn  is  passed.  The  size  in  the 
box  is  then  "fed  up"  with  2  to  4  gallons  of  the 
boiled  size,  The  operation  of  "feeding  up"  is 
repeated  after  every  20  pounds  of  yarn  has  been 
treated. 


444      The  Chemistry  and  Practice  of  Sizing. 

For  the  first  time  of  sizing  it  is  not  customary  to 
use  tallow  or  other  softener.  In  the  second  operation 
a  44  mixing  "  similiar  to  the  first,  but  weaker,  is  made. 
To  this  should  be  added  from  i  to  2  pounds  of 
tallow  or  paraffin  wax.  The  strength  of  the  size  for 
the  second  operation  depends  upon  the  counts  of 
yarn  being  treated,  but  it  is  always  weaker  than  the 
44  mixing"  used  for  the  first  operation. 

The  yarn  should  not  be  overwrung  the  first 
time  of  sizing,  and  it  should  be  placed  straight 
on  the  stove  poles  and  dried.  If  the  operation  be 
properly  carried  out  the  yarn  should  come  from  the 
drying  chambers  very  stiff  and  "boardy."  It  should 
be  well  wrung  after  the  second  operation.  After 
wringing  it  is  shaken  out  on  the  wringing  or  shaking 
post.  The  finer  counts  of  yarn  should  be  brushed 
either  with  a  brush  similar  to  a  warp  dressers  brush, 
or  on  a  brushing  machine,  such  as  shown  in  the 
illustration  on  page  445.  After  brushing,  it  is  carried 
on  the  44 shaking  stick"  and  placed  open  and  straight 
on  the  stove  poles  to  dry. 

Grey  yarn,  after  being  boiled  in  water  as 
previously  described  on  page  438,  is  treated  as 
above,  but  a  stronger  size  should  be  used  in 
this  case. 

During  the  sizing  process,  the  hanks  are  liable 
to  become  disarranged.  It  is  therefore  necessary 
to  straighten  the  yarn  and  44 lay"  the  fibres,  and,  at 
the  same  time,  stretch  the  hanks  to  something  like 


44^      The  Chemistry  and  Practice  of  Sizing. 

their  original  dimensions.  This  operation  is 
performed  after  the  final  sizing,  but  it  will  be  better 
described  before  discussing  the  drying  operation. 

For  a  long  time  brushing  and  stretching  have 
been  carried  out  by  hand,  but  these  operations  may  be 
more  successfully  carried  out  by  means  of  the  brush- 
ing and  stretching  machine  shown  on  page  445. 

The  hanks  are  laid  over  the  two  sets  of  copper 
rollers.  This  is  done  by  raising  the  lower  set  of 
rollers  by  means  of  a  hand  lever,  shown  in  the 
illustration.  A  catch  holds  the  lever  in  position 
until  it  is  necessary  to  lower  it. 

The  upper  set  of  rollers  revolves  at  a 
regular  speed.  The  lower  set  are  rotated 
intermittently  by  the  action  of  the  yarn,  but 
they  receive  a  vertically  reciprocating  motion 
which,  at  the  upper  end  of  the  stroke  (when  the 
brushes  are  on  the  return  stroke),  takes  the  weight 
of  these  rollers  off  the  hanks.  This  motion  is 
effected  by  a  cam  not  shown  in  the  illustration. 

Inside,  and  behind  each  set  of  hanks  are 
reciprocating  brushes  so  arranged  that  one  set 
brushes  one  side  and  the  other  set  the  other  side  of 
the  hank.  Their  movement  is  not  quite  vertical,  for 
they  come  in  contact  with  the  yarn  on  the  downward 
stroke  only,  and  are  quite  clear  of  it  when  moving 
upward. 

The  brush  motion  is  weighted  to  meet  the 
heavy  work  put  upon  it  at  the  times  the  brushes  are 


"Hank  Sizing' — Brushing  Machine.  447 

passing  through  the  yarn,  and  so  enables  the 
machine  to  run  at  a  regular  speed.  The  brushing 
movement  is  arranged  so  as  to  cope  with 
emergencies.  In  case  of  a  "felter"  in  the  yarn, 
through  which  the  brushes  would  not  pass  without 
breaking  the  threads,  the  brushes  "give,"  and  thus 
avoid  causing  damage.  The  rollers,  or  arms,  work 
in  a  parallel  motion,  thus  stretching  the  yarn 
evenly.  The  position  of  the  lower  set  of  rollers 
is  adjusted  by  the  length  of  the  hank,  of  which 
various  sizes  can  be  taken  without  altering  the 
machine. 

The  speed  of  this  brushing  machine  is  very  high 
and  the  output  from  it  is  very  large. 

After  sizing,  the  hanks  are  dried  in  the  stove. 
The  stove  used  for  this  purpose  is  generally  a  brick 
building,  with  one  or  two  floors.  Each  floor  usually 
contains  two  tiers.  The  floors  are  constructed  of  iron 
gratings,  so  that  the  air  may  pass  upwards  from 
the  basement  and  out  at  the  top  of  the  building 
through  a  ventilator. 

The  drying  operation  is  generally  carried  out  at 
night  so  that  the  hanks  may  be  ready  for  re-sizing 
the  next  day.  Drying  by  means  of  a  stove,  or  hot- 
air  chamber,  is  not  an  ideal  method,  as  it  often 
leads  to  damage  through  the  hanks  becoming  "soft," 
This  damage  is  caused  through  the  air  being 
insufficiently  circulated  through  the  stove.  The 
conditions  suitable  for  bacterial  development  are 


448      The  Chemistry  and  Practice  of  Sizing, 


provided  by  the  moisture  and  the  high  temperature, 
and  the  size  loses  its  adhesiveness.  If  this 
occurs  the  operation  of  sizing  has  to  be  repeated, 
otherwise  the  yarn  would  not  weave.  The 
damage  would  not  take  place  in  a  well  ventilated 
stove,  and  for  this  reason  fans  are  very  often 
employed  to  remove  the  air.  This  is  not  always 
convenient,  however,  on  account  of  the  difficulties 
of  driving.  There  is  a  further  objection  to  the  use 
of  fans  in  large  manufacturing  centres.  The  fans 
draw  into  the  stove  particles  of  soot  and  dirt,  and 
unless  the  air  be  filtered  these  particles  are  deposited 
on  the  yarn. 

There  are  several  firms  in  this  country  who  are 
making  an  improved  form  of  drying  apparatus.  The 
chief  advantages  are  that  the  drying  can  be  carried 
out  in  the  day-time,  and  there  is  less  liability  to 
produce  "soft"  yarn.  Such  apparatus  is  also  free 
from  the  troubles  caused  by  the  use  of  fans  as 
previously  mentioned. 

Such  in  brief  are  the  chief  operations  involved  in 
hank  sizing,  but  the  success  of  the  operations  depend 
mainly  on  two  conditions,  the  first  is  that  the  "sizer" 
should  be  a  man  who  knows  his  work,  and  the  second 
is  that  the  ingredients  should  be  suitable.  However 
skilful  a  workman  may  be  he  cannot  get  good  results 
from  unsuitable  ingredients,  and  however  suitable  the 
ingredients  may  be  good  results  cannot  be  got  unless 
the  "sizer"  knows  his  business. 


"Hank  Bleaching." 


449 


It  has  already  been  stated  that  a  pure  flour  of 
good  quality  should  be  used,  and  it  has  also  been 
mentioned  that  the  size  mixing  should  be  well  boiled, 
Better  results  would  be  obtained  in  hank  sizing"  if 
manufacturers  would  put  down  suitable  plant  for 
steeping  the  flour  so  that  the  starch  could  be  properly 
separated  from  the  gluten  as  is  done  in  tape  sizing. 
Most  of  the  troubles  of  hank  sizers  are  due  to  the 
use  of  unsuitable  ingredients  or  to  unsuitable  methods 
of  treating  the  ingredients. 

HANK  BLEACHING. 

The  process  of  bleaching  in  the  hank  is  carried 
out  as  follows  : — 

The  hanks  are  first  tied  up  into  bundles  of  10  lbs. 
each  and  afterwards  boiled  in  the  open  kier  with  a 
solution  of  soda  ash  and  caustic  soda  as  described 
on  page  424.  The  bleaching  operations  may  be 
summarised  as  follows  : — 

1st.  —  Kier  boiled  for  about  10  to  12  hours  with 
soda  ash  and  caustic  soda. 

2nd.— Washed  with  water  in  the  kier. 

3rd. — "Chemicked." 

4th. — Washed  with  water  in  the  "chemic"  cistern. 
5th. — "  Soured"  in  acid  in  the  "chemic"  cistern. 
6th. — Washed  with  water  in  the  "chemic"  cistern. 
7th. — Soaped  and  "blued." 

8th. — Treated  in  the  "stocks"  or  in  the  "dumper." 
9th. — Washed  with  water. 

C2 


450      The  Chemistry  and  Practice  of  Sizing. 

After  boiling  in  the  kier  the  liquor  is  drained  off. 
The  first  washing  is  conducted  in  the  kier  and  the 
wash  water  drained  off  as  far  as  possible,  The  top 
bundles  may  then  be  placed  in  the  "chemic"  cistern, 
as  they  will  be  sufficiently  dried  for  treatment,  but 
the  bottom  bundles  must  be  hydro-extracted,  other- 
wise the  bleaching  liquor  will  not  penetrate  the 
yarn,  and  the  excess  of  water  contained  in  the 
hanks  would  dilute  the  bleaching  liquor  to  such  an 
extent  as  to  make  it  inoperative. 

When  the  bundles  of  yarn  have  been  placed  in  the 
"chemic"  cistern,  the  bleaching  liquor,  which  should 
be  used  at  about  i°  Tw.,  is  sprayed  or  showered  over 
them  by  means  of  a  pump  for  three  or  four  hours, 
according  to  the  weight  of  yarn  undergoing  treatment. 

After  "  chemicking"  the  hanks  are  allowed  to 
drain  thoroughly  and  then  water  is  showered  over 
them  by  means  of  the  pump  in  order  to  remove  the 
last  trace  of  "chemic."  The  washing  operation 
should  be  carried  out  at  intervals,  as  better  results 
can  be  obtained  by  working  the  pump  for  20  minutes, 
allowing  the  washing  liquor  to  drain  off  well  and 
afterwards  pumping  fresh  water  over,  than  can  be 
got  by  working  the  pump  continuously.  This 
method  effects  a  considerable  saving  in  the  water 
also. 

After  washing  off  from  the  " chemic"  the  hanks 
are  "showered"  with  acid,  Twaddelling about  i°  Tw. 
This  operation  is  conducted  in  the  same  cistern  as 


"Hank  Bleaching!' 


45i 


that  used  for  "chemicking"  and  washing,  and  should 
be  continued  for  about  an  hour,  according  to  the 
weight  of  yarn  undergoing  treatment. 

After  "souring,"  the  hanks  are  allowed  to  drain 
well,  and  afterwards  thoroughly  washed,  as  previously 
described,  in  order  to  remove  all  trace  of  acid.  They 
are  then  soaped  and  "blued"  if  required.  From  the 
soap  bath  the  hanks  are  placed  in  the  "stocks"  where 
they  are  beaten  or  pounded  by  wooden  beaters  for 
some  time.  This  operation  is  very  effectual  for 
removing  the  last  trace  of  dirt.  After  "stocking," 
the  hanks  are  washed  and  drained,  and  finally  treated 
in  the  hydro-extractor.  This  latter  operation  is 
absolutely  essential  as  the  yarn  would  be  too  wet  to 
size  after  draining  only.  The  excess  of  water  would 
weaken  the  size  to  such  an  extent  as  to  cause  the 
yarn  to  come  up  "soft,"  Not  only  would  this  be  the 
case  but  it  would  be  impossible  for  the  size  to 
penetrate  yarn  saturated  with  moisture.  An  illus- 
tration of  one  of  the  best  types  of  hydro-extractors 
is  shown  on  page  452. 

The  hydro-extractor  is  a  machine  employed  for 
removing  water  or  other  liquid  from  some  material 
by  the  action  of  centrifugal  force. 

The  material  from  which  the  water  has  to  be 
extracted  is  put  into  a  cylindrical  vessel,  usually 
called  the  basket  of  the  machine,  the  shell  or 
periphery  of  which  is  perforated.  The  basket  is 
then  revolved  at  a  high  speed  and  the  centrifugal 


452      The  Chemistry  and  Practice  of  Sizing. 

force  presses  the  material  against  the  shell,  thus 
expelling  the  water  through  the  perforations  into  a 
suitable  outer  case. 

These  hydro-extractors  may  be  either  of  the 
pivot  or  under-driven  type,  or  of  the  suspended  or 
over-driven  type,  but  when  a  large  machine  is 
required  the  suspended  type  is  preferable.  Either 


Suspended  Type  of  Hydro-Extractor. 
Watson,  Laidlaw  &  Co.  Ltd.,  Glasgow. 

type  of  machine  may  be  driven  by  belt  from  a  shaft, 
or  by  an  engine,  or  by  an  electro  motor.  The 
suspended  machines  may  also  be  driven  by  an  electro 
motor  coupled  direct  to  the  extractor  spindle. 

The  electro  motors  are  totally  enclosed  to  permit 
them  being  worked  in  a  damp  atmosphere,  and  either 


The  Hydro- Extractor. 


453 


continuous  current  or  alternating  current  motors 
may  be  used. 

The  machines  may  also  be  driven  by  a  water 
motor  coupled  direct  to  the  extractor  spindle.  The 
water  pressure  is  usually  from  150  to  200  lbs.  per 
square  inch  and  supplied  by  a  pump  put  in  for  the 
purpose.  In  some  instances  the  pump  required  for 
the  fire  extinguishing  apparatus  is  used. 

In  the  direct  electrically-driven  machines,  and 
those  driven  by  water,  there  is  an  entire  absence  of 
belting  and  shafting,  which  is  a  great  advantage  as 
they  may  be  placed  in  any  convenient  position 
independent  of  shafting,  and  the  work  done  by  the 
machines  driven  in  any  of  the  described  methods  is 
the  same. 

In  the  machine  illustrated,  all  the  parts  are  above 
the  ground  level,  and,  as  they  are  self-balancing,  a 
special  foundation  is  not  required.  The  machines 
may  also  be  placed  on  any  upper  floor  which  will 
carry  ordinary  machinery  of  like  weight. 

The  self-balancing  feature  is  obtained  by  em- 
bracing one  end  of  the  spindle  in  an  indiarubber 
buffer  or  cushion  placed  at  the  top  of  the  spindle  in 
suspended  machines,  and  at  the  lower  end  in  pivot 
machines.  This  buffer,  which  is  patented,  is  conoidal 
in  form,  and  it  is  a  great  improvement  over  forms  of 
buffers  hitherto  used.  Not  only  is  it  self-adjusting, 
but  it  controls  the  oscillations  of  the  machine  better 
than  other  types. 


454      The  Chemistry  and  Practice  of  Sizing. 

The  spindles  are  made  in  one  piece,  and  the  load 
and  side  pressure  is  taken  by  an  arrangement  of  ball 
bearings.  There  are  no  brass  bushes  and  the  ball 
bearings  do  not  require  to  be  lubricated  in  the 
ordinary  sense.  It  is  only  necessary  to  have 
sufficient  grease  on  them  to  prevent  rusting.  In 
this  condition  they  will  run  for  several  months 
without  requiring  the  supply  of  grease  to  be 
replenished. 

The  baskets  in  the  type  of  machine  showrn  in  the 
illustration  hold  more  than  those  of  other  makes 
because  they  have  no  cone  in  the  centre.  They  have 
wider  lips  and  they  are  also  deeper,  especially  the 
suspended  machines,  than  those  of  the  pivot  type. 
The  baskets  of  the  former  type  are  also  deeper. 

The  pivot  machines  are  made  with  the  following 
diameters  of  baskets: — 18,  21,  24,  27,  30,  36  and 
42  inches,  while  the  usual  sizes  of  suspended  machines 
are  24,  30,  36,  42,  48,  54  and  60  inches,  but  special 
suspended  machines  are  also  made  with  baskets 
72  and  84  inches  diameter. 


Preparation  of  the  Yarn  for  Weaving.  455 


Chapter  XI. 

The  Preparation  of  the  Yarn  for  the 
Process  of  Weaving, 

and 

The  Testing  of  Sized  Yarns. 

THE  preparation  of  the  yarn  previous  to  its 
being  woven  into  cloth  demands  more  care 
and  attention  than  the  actual  process  of  weaving. 
Careless  treatment  of  the  yarn  in  the  winding  and 
warping  operations  entails  extra  work  by  the 
weavers.  Big  knots  taken  up  carelessly  in  winding, 
or  lost  ends,  and  bad  sides  in  warping,  are  a  few  of 
the  faults  which  tend  to  increase  the  weavers  work. 
If,  in  addition  to  these  faults  the  yarn  has  been 
badly  sized,  or  if  the  "elasticity"  has  been  taken  out 
of  it  through  too  much  tension,  or  worse  still,  if  it 
has  been  dried  to  such  an  extent  as  to  deprive  it  of 
the  greater  portion  of  its  natural  moisture,  the 
weaver  will  have  still  further  trouble.  At  the  same 
time  there  is  no  method  of  sizing  known  by  which 
bad  or  indifferent  yarn  can  be  made  to  weave  as 
well  as  good  yarn,  nor  has  any  method  of  applying 
the   size,   or   any  special  sizing  ingredient  been 


456      The  Chemistry  and  Practice  of  Sizing. 

discovered,  which  will  enable  "heavy"  sized  yarn  to 
wTeave  as  well  as  "pure"  sized  yarn.  Anyone  who 
can  discover  such  a  process,  or  such  a  sizing 
ingredient,  will  be  a  benefactor  to  thousands  in 
Lancashire. 

The  aim  and  object  of  all  operations  involved  in 
the  preparatory  processes  should  be  to  treat  the 
yarn  in  such  a  manner  as  to  get  rid  of  its  defects, 
such  as  lumps,  loose  ends,  and  weak  places.  At 
the  same  time  every  possible  precaution  should 
be  taken  to  keep  the  strength  and  "elasticity" 
unimpaired.  If  only  a  little  more  time  and  thought 
were  devoted  by  all  operatives  to  considering  the 
welfare  of  those  who  follow  them  in  the  after 
processes,  the  quality  of  work  would  be  improved 
all  round.  No  single  operative  can  do  more 
towards  this  end  than  the  "taper."  He  can  see  by 
the  appearance  of  the  yarn  as  it  travels  along  the 
headstock  whether  the  lumps  and  loose  ends  have 
been  taken  out.  The  number  of  'Mappers "  on  the 
backbeams  will  also  give  him  an  idea  as  to  the 
quality  of  the  yarn  and  the  relative  merits  of  the 
different  warpers  for  making  good  work. 

Weavers  cannot,  as  a  rule,  understand  that 
"ends  which  come  up  broken"  are  due  to  careless 
warpers  taking  "ends"  up  "crooked,"  and  so  causing 
"lappers."  The  taper  gets  the  blame  for  this,  and 
all  tapers  would  be  acting  in  their  own  interests 
and  in  the  interests  of  their  employers  if  they  tried 


Preparation  of  the  Yarn  for  Weaving.  457 

to  keep  the  warpers'  work  up  to  the  highest  possible 
standard. 

If  the  automatic  loom  has  to  be  introduced  into 
Lancashire  with  a  view  to  decreasing  the  cost  of 
production  by  increasing  the  number  of  looms  per 
operative,  the  quality  of  the  work  on  the  weavers 
beam  will  certainly  have  to  be  improved.  How 
much  of  this  improvement  can  be  obtained  by 
reducing  the  speed  of  the  machinery  remains  to  be 
seen.  Without  doubt  the  whole  of  the  machinery 
in  the  weaving  department  is  being  run  at  a  high 
speed  with  a  view  to  producing  the  maximum 
amount  of  work  per  machine  in  a  given  time. 
Whether  this  speed  is  the  right  one  for  obtaining  a 
maximum  output  per  operative  is  another  question 
altogether.  If  the  speed  of  the  warping  mills  and 
the  looms  were  decreased  the  amount  of  labour 
expended  in  piecing  broken  yarn  would  certainly 
be  considerably  reduced,  At  the  same  time  it  must 
not  be  forgotten  that  however  much  the  speeds  of 
these  machines  are  reduced,  or  how  careful  each 
operative  may  be,  the  chief  requisite  for  producing 
a  perfect  weavers  beam  is  good  strong  yarn. 

Lancashire  manufacturers  have  endeavoured  to 
produce  cloth  which  shall  have  as  full  an  appearance 
as  it  is  possible  to  obtain  from  the  counts  of  yarn 
woven  into  it.  In  order  to  produce  this  condition  it  is 
essential  that  the  yarn  shall  be  spun  with  less  turns 
per  inch  than  is  required  for  producing  a  yarn 


458      The  Chemistry  and  Practice  of  Sizing. 

possessing  the  maximum  strength.  The  strength 
of  the  yarn  is  thus  sacrificed  in  order  to  obtain  an 
increased  diameter  of  thread.  Yarn  of  this  descrip- 
tion may  give  a  "full"  appearance  to  the  cloth,  but 
it  is  responsible  for  an  enormous  amount  of 
unnecessary  work  to  those  engaged  in  manipulating 
it.  The  cloth  may  look  better  but  it  probably  does 
not  wear  so  well.  The  number  of  extra  ends  pieced 
by  winders,  warpers,  and  weavers,  through  the  use 
of  this  soft,  and  often  unevenly  twisted  mule  yarn, 
is  undoubtedly  a  waste  of  energy  which  might  be 
put  into  more  remunerative  channels. 

If  operatives  are  expected  to  superintend  more 
machines  it  is  evident  to  the  authors  that  the 
"full"  appearance  of  the  cloth  will  have  to  be  taken 
less  into  consideration,  or  this  appearance  will  have 
to  be  produced  by  some  process  after  the  cloth  is 
woven. 

Ring  spun  yarn  does  not  give  so  full  an  appear- 
ance to  the  cloth  as  mule  spun  yarn.  It  contracts 
more  in  length  during  the  process  of  weaving,  and 
it  also  requires  a  stronger  size  than  mule  spun  yarn 
to  put  a  given  percentage  on  the  yarn.  On  the 
other  hand  it  is  more  uniform  in  diameter,  strength, 
and  turns  per  inch.  Its  breaking  strain  is  also 
higher,  and  it  contains  a  less  number  of  thin  and 
soft  places.  For  these  reasons  it  weaves  with 
less  breakages  than  the  average  mule  yarn,  and 
it  is  therefore  more  suitable  for  an  automatic  loom. 


The  Testing  of  Sized  Yarns.  459 


In  order  to  reduce  the  amount  of  labour  required 
in  all  the  processes  involved  in  the  weaving  section 
of  the  cotton  industry  to  a  minimum,  it  will  be 
necessary  that  the  yarn  shall  be  evenly  spun  and 
free  from  ''snarls,"  in  order  to  obtain  the  maximum 
amount  of  strength  uniformly  distributed  throughout 
its  entire  length. 

THE  TESTING  OF  SIZED  YARNS. 

Efforts  have  been  made  at  various  times  to 
introduce  a  system  for  testing  yarn  before  and 
after  sizing  for  "elasticity"  and  strength.  The 
differences  are  generally  given  in  terms  of  "per- 
centage of  gains  in  strength,"  and  "percentage 
loss  or  gain  in  elasticity." 

For  the  purpose  of  testing  yarns  many  machines 
have  been  placed  upon  the  market,  but  what- 
ever merit  they  may  possess  when  employed  for 
testing  the  strength  of  unsized  yarn,  they  are  of  no 
practical  use  for  testing  the  weaving  qualities  after 
it  has  been  sized.  There  are  many  points  to 
consider  when  testing  the  weaving  qualities  of  a 
sized  yarn  besides  the  breaking  strength,  and  the 
only  reliable  test  is  the  actual  weaving  of  the  yarn 
into  cloth.  The  usual  method  adopted  by  the 
manufacturer  is  to  note  the  "feel"  of  the  yarn  after 
it  has  been  sized.  This,  together  with  careful 
observation  as  to  the  manner  it  weaves  in  the  shed, 
are  the  only  reliable  tests  which  can  be  applied  as  yet. 


460      The  Chemistry  and  Practice  of  Sizing, 

The  authors  are  strongly  of  the  opinion  that  the 
results  obtained  with  any  type  of  testing  machine 
are  not  a  reliable  indication  of  the  weaving 
qualities  of  the  yarn.  In  the  first  place  -  the 
amount  of  size  present  affects  the  results  shown 
on  the  testing  machine.  Thus,  if  the  yarn  is 
<lpure"  sized  the  "gain  in  strength,"  as  shown  by 
the  testing  machine,  will  depend  to  a  very  great 
extent  upon  the  amount  of  size  which  has  been 
incorporated  with  it,  the  greater  the  percentage  of 
size  and  the  greater  will  be  the  apparent  "gain 
in  strength."  It  does  not  necessarily  follow,  how- 
ever, that  if  5  per  cent,  of  size  on  the  twist  is 
sufficient  for  a  certain  class  of  cloth  that  it  is 
advantageous  to  size  it  to  the  extent  of  10  per  cent. 
The  latter  amount  of  size  wrould  show  a  better 
result  when  tested  on  the  testing  machine,  but  this 
does  not  mean  that  it  would  weave  any  better \  All 
practical  sizers  know  that  it  is  necessary  to  size 
yarn  according  to  the  class  of  cloth  it  is  intended 
to  produce.  For  instance,  size  which  would  be 
suitable  for  a  fine  reed  and  a  large  number  of  picks 
would  not  be  suitable  for  a  coarse  reed  and  a 
correspondingly  lower  number  of  picks.  In  the 
former  case  the  size  would  require  to  be  stronger 
than  in  the  latter.  But  if  a  strong  size  were  used 
for  a  coarse  reed  and  a  low  pick,  thus  giving  a 
greater  percentage  of  size,  it  would  not  weave  as 
well  as  a  weaker  size,  nor  would  it  produce  a  cloth 


The  Testing  of  Sized  Yarns.  461 


with  as  good  a  "cover,"  although  it  would  show7  a 
greater  breaking  strength  on  the  testing  machine. 

The  term  "  elasticity "  has  been  used  in  the 
previous  chapters  of  this  book  on  many  occasions. 
The  authors  have  used  the  term  simply  because  it 
is  a  customary  one.  At  the  same  time  it  is  not 
correctly  used  when  applied  to  the  testing  of  yarns, 

"Elasticity"  means  the  power  possessed  by 
bodies  to  return  to  the  form  from  which  they  have 
been  bent  or  distorted.  In  testing  yarns  for  what  is 
termed  "elasticity,"  it  is  usual  to  stretch  the  yarn 
until  it  breaks.  In  other  words  the  "elasticity"  is 
confounded  with  the  breaking  strain. 

The  difference  in  length  between  the  yarn  in 
its  natural  condition  as  a  thread,  and  the  distance 
it  will  stretch  before  breaking,  should,  in  the  opinion 
of  the  authors,  be  termed  "the  percentage  of 
elongation,"  and  not  "the  percentage  of  elasticity." 

The  amount  of  "elongation"  depends  upon 
several  conditions.  It  is  governed  in  the  first  place 
by  the  length  of  the  fibres  which  compose  the  thread; 
in  the  second  place  by  the  evenness  and  the  number 
of  turns  of  "twist"  imparted  to  the  thread; 
in  the  third  place  by  the  percentage  of  size  in- 
corporated with  the  yarn,  and  lastly  by  the  amount  of 
moistwe  contained  in  the  yarn  at  the  time  it  is  tested. 

The  authors  know  of  many  instances  where 
samples  from  the  same  yarn  have  given  entirely 
different  results  when  tested  on  the  same  machine. 


462      The  Chemistry  and  Practice  of  Sizing. 

They  also  know  many  cases  where  yarns  have 
been  tested,  and  the  samples  showing  the  worst 
result  on  the  testing  machine  have  given  the  best 
results  in  the  weaving  shed,  and  vice  versa. 

Not  only  do  the  majority  of  the  testing  machines 
give  results  which  are  unreliable  for  practical 
working,  but  they  all  fail  to  take  into  consideration 
one  of  the  most  important  factors  in  the  weaving 
quality  of  a  well  sized  yarn,  viz.: — its  pliability. 

The  pliability  of  a  sized  yarn  determines  to  a 
great  extent  its  weaving  qualities.  The  difference 
shown  in  the  weaving  of  the  same  yarn  on  a  dry 
windy  day  and  on  a  calm  moist  day  is  due  entirely 
to  the  difference  in  the  pliability  of  the  yarn  on 
these  days.  During  the  process  of  weaving  the 
yarn  is  being  bent  continually  from  the  point  where 
it  gets  to  the  shed  rods  to  the  point  where  it 
reaches  the  fell  of  the  cloth.  No  matter  how  strong 
the  yarn  may  be  it  will  not  weave  satisfactorily  if  it 
does  not  possess  the  necessary  pliability.  In  this 
respect  it  may  be  compared  with  the  results  which 
would  be  obtained  if  a  piece  of  strong  cardboard 
were  tested  for  breaking  strength  against  a  piece  of 
tissue  paper.  The  cardboard  would  be  far  stronger 
if  subjected  to  a  straight  pull  but  if  they  were  tested 
for  breaking  strength  by  bending  each  at  right 
angles  the  tissue  paper  would  show  a  much  better 
result  than  the  cardboard. 


The  Cotton  Fibre. 


463 


Chapter  XII. 

The  Physical  and  Chemical  Properties 
of  Cot  toil, 

and  the 

Chemical 1  Examination  of r  Textile Fibres 


COTTON  forms  the  seed  hairs  of  various  kinds 
of  Gossypium  of  the  natural  order  Malvacoe. 
The  most  important  species  are : — 

1.  Gossypium  herbaceum. — This  is  an  annual 
shrubby  plant,  about  three  feet  high,  indigenous  to 
Asia  and  Egypt.  A  drawing  of  this  plant  is  shown 
on  page  464. 

2.  Gossypium  barbadense. — This  plant  reaches 
a  height  of  fifteen  feet;  indigenous  to  the  West 
Indies. 

3.  Gossypium  religiosum. — This  species  has  a 
brownish  yellow  fibre;  indigenous  to  India  and 
China. 

4.  Gossypium  hirsutum. — The  hairy  American 
cotton  grows  to  a  height  of  about  six  feet.  It  is 
largely  cultivated  in  North  and  South  America. 


464      The  Chemistry  and  Practice  of  Sizing. 


The  fibres  of  cotton  are  unicellular,  consisting  of 
hollow  tubes.  They  are  easily  recognised  by  means 
of  the  microscope,  and  readily  distinguished  from 


Cotton  Pod  and  Flower  of  Gossypium  Herbaceum. 

other  fibres  such  as  flax  and  jute  hemp.  The 
diameters  and  lengths  of  the  fibres  vary  very  con- 
siderably in  different  kinds  of  cotton. 


LIST  OF 

MAGNIFIED  TEXTILE  FIBRES. 


No.   1.— Plate  XV  Magnified  Cotton  Fibres. 


No. 

2.—  „ 

XVa  „ 

Mercerised  Cotton  Fibres. 

No. 

3.—  „ 

XVb 

Dead  Cotton  Fibres. 

No. 

4.—  , 

XVI  „ 

Flax  Fibres. 

No. 

5.—  „ 

XVIa  „ 

Hemp  Fibres. 

No. 

6—  , 

XVII  „ 

Jute  Fibres. 

No. 

7.—  „ 

XVIIa  „ 

Wool  Fibres. 

No. 

8.—  „ 

XVIIb  „ 

China  Grass  (Ramie)  Fibres. 

No. 

9.—  , 

XVIII  „ 

Raw  Silk  Fibres. 

No.  10.—  , 

XVIIIa  „ 

Viscose  Fibres. 

Photographs  and  Drawings  by 
Flatters,  Milborne  &  McKechnie  Limited,  Manchester. 


Cotton  Fibre  x  100. 
Plate  XV. 


Transverse  Section  Mercerised  Cotton  Fibre  x  100. 


Mercerised  Cotton  Fibre  x  100. 

Plate  XVa. 


Transverse  Section  of  Fibres  of  Dead  Cotton  X  100. 


Photomicrograph  of  Dead  Cotton  x  75. 
Plate  XVb. 


Transverse  Section  of  Flax  Fibre  x  100. 
In  natural  bundle  masses. 


Flax  Fibre  x  100. 

Fibres  partially  separated. 
Plate  XVI. 


Hemp  Fibre  x  100, 
Reduced  to  single  Fibres. 
Plate  XVIa. 


Transverse  Section  of  Jute  Fibre  x  100. 

In  natural  bundle  masses. 


Jute  Fibre  X  100. 

Reduced  to  ultimate  Fibres. 
Plate  XVII. 


Lincoln  Hog  X  65. 


Wool  Saxony  X  65. 
Plate  XVIIa. 


China  Grass  (Rhamie)  X  60. 
Plate  XVIIb. 


Transverse  Section  of  Raw  Silk  x  200. 


Entire  Fibre  of  Raw  Silk  x  75. 
Plate  XVIII, 


n 


C 


9 


o 


0 

Q) 

o 

<3 

3  r 

Transverse  Section  of  Viscose  Fibres  x  100 

(Artificial  Silk.) 


Entire  Fibres  of  Viscose  x  100 

(Artificial  Silk.) 

Plate  XVIIIa. 


Cotton  Fibre. 


465 


The  following  table  will  give  the  reader  some 
idea  of  the  average  size  of  the  different  classes: — 


Length.  Diameter. 


South  Sea  Islands  . , 

, .  1  "68  inch 

1 

1  5  6  2 

of  an 

Egyptian   

...1-25  „ 

1 

1  5  2  6 

United  States   

...roo  „ 

1 

1  2  !)  0 

>> 

Indian   

...094  „ 

1 

118  5 

Cotton  used  for  "heavy"  sized  yarn  should 
be  medium  in  length  of  staple,  and  should  not 
be  too  tightly  spun.  American  cotton  is  almost 
invariably  used  for  this  purpose. 

Chemically,  cotton  fibre,  separated  from  all 
impurities,  may  be  looked  upon  as  pure  cellulose 
similar  in  chemical  composition  to  the  cellulose  in 
starch  and  wood,  and  having  the  same  approximate 
composition,  usually  expressed  by  the  empirical 
formula  C6H10O5.  The  following  is  the  percentage 
of  the  elements,  carbon,  hydrogen,  and  oxygen, 
which,  chemically  combined,  form  cellulose  : — 

Carbon    44*44 

Hydrogen   6*17 

Oxygen   49-38 

99*99 


Ordinary  raw  cotton  is  not  pure  cellulose.  It 
contains  various  impurities  such  as  wax,  oil, 
colouring  matter,  water,  and  about  one  per  cent, 
of  mineral  matter. 

D2 


466      The  Chemistry  and  Practice  of  Sizing, 


The  following  may  be  taken  as  the  average 
percentage  composition  of  ordinary  raw  cotton  :  — 

Pure  dry  cellulose      87 

Wax,  oil,  colouring  matter  .......  4 

Mineral  matter,  as  ash    1 

Natural  moisture   8 

100 


Cellulose. — The  cellulose  of  cotton  consists  of 
the  cuticula,  or  skin,  and  cellulose  proper.  This  is 
shown  by  the  action  of  ammoniacal  copper  oxide 
solution  which  dissolves  the  cellulose,  causing  it 
to  swell  up,  leaving  the  cuticula  broken  but 
unchanged.  On  adding  sulphuric  acid,  and  after- 
wards a  drop  of  solution  of  iodine,  the  cellulose  is 
coloured  blue,  the  broken  cuticula  yellow. 

Cellulose  is  insoluble  in  cold  or  hot  water,  in 
dilute  acids  or  alkalies,  in  ether,  alcohol,  fats,  or 
volatile  oils,  but  it  is  readily  dissolved  in  concen- 
trated sulphuric  acid,  and  in  very  strong  solutions 
of  caustic  alkalies.  A  very  interesting  fact  is  that 
cellulose  has  the  property,  when  immersed  in 
solutions  of  weak  mineral  acids,  of  absorbing  and 
condensing  the  acid  within  itself  at  the  expense  of 
the  surrounding  liquor,  which  is  made  weaker  in 
consequence.  This  is  an  important  matter  to  the 
bleacher,  showing  that  strong  solutions  of  acids 
must  not  be  used  nor  must  the  cloth  remain  long  in 
contact  with  the  " souring  liquor,"  even  when  dilute. 


Cotton — Mineral  Matter  contained  in.  467 

Dilute  mineral  acids  as  previously  stated  do  not 
attack  the  cellulose  of  cotton,  but  if  the  fabric  con- 
taining weak  acid  be  subjected  to  dry  heat  tender- 
ing takes  place. 

Cellulose  is  not  effected  by  milk  of  lime  either 
hot  or  cold  so  long  as  it  be  immersed  in  the 
liquid,  but  if  the  lime  be  allowed  to  dry  on  the  fibre, 
or  if  the  fibre  be  exposed  to  the  atmosphere,  it  soon 
tenders  through  the  formation  of  oxycellulose.  This 
is  a  matter  which  is  also  of  the  greatest  importance 
in  the  bleaching  of  cotton  and  linen  cloth. 

Mineral  Matter. — The  mineral  matter  in  cotton 
as  previously  stated,  is  about  one  per  cent.  The 
following  analysis  of  the  ash  shows  its  average 
composition : — 


  44*So  | 

Soluble 

Chloride  of  potassium   

  9'9o  f 

in 

Sulphate  of  potassium   , 

  9'3°  ) 

Water. 

Phosphate  of  magnesium   

  8'4o  1 

Phosphate  of  calcium   

  9'°°  1 

Insoluble 

Carbonate  of  calcium   

  io'6o  y 

in 

Peroxide  of  iron  

  3'°°  1 

Water. 

Alumina,  traces  and  loss   

  5'ooJ 

IOO'OO 

The  above  analysis  represents  the  ash  after 
burning.  It  is  highly  probable  that  the  phosphoric 
acid  is  combined  with  some  of  the  potassium,  and 
the  magnesium  with  hydrochloric  acid,  as  all  natural 
cotton  yields  from  0*04  to  0*08  per  cent,  of 
chloride  of  magnesium  when  digested  with  distilled 


468      The  Chemistry  and  Practice  of  Sizing. 

water.  This  together  with  the  carbonate  of  potassium 
accounts  for  the  hygroscopic  nature  of  natural  cotton. 

Oil,  Wax,  Resin,  Etc. — These  substances,  to- 
gether with  certain  soluble  matters,  are  found  in  and 
upon  raw  cotton  to  the  extent  of  about  four  per  cent. 
It  is  due  to  the  presence  of  these  waxy  and  oily  matters 
that  raw  cotton  and  unbleached  cotton  yarns  and 
cloth  are  so  difficult  to  wet  through  with  water. 

The  late  Dr.  Edward  Schunck  of  Manchester 
examined  raw  cotton  with  a  view  to  determine  the 
nature  of  the  substances  contained  in  cotton  fibre 
other  than  cellulose.  Dr.  Schunck  found  amongst 
other  substances  a  wax  which  he  called  cotton  wax. 
This  has  a  melting  point  of  over  186°  Fah.  He  also 
obtained  a  white  solid  fatty  acid,  having  a  melting 
point  of  1 32°  Fah.;  two  distinct  colouring  matters, 
one  soluble  the  other  insoluble  in  alcohol  ;  pectic 
acid,  and  albuminous  matters.  Most  of  these  sub- 
stances are  practically  insoluble  in  water,  and  it  is  on 
this  account  that  the  principal  processes  in  bleaching 
consist  of  operations  designed  to  remove  the  resinous, 
oily,  and  waxy  substances.  They  protect  the 
colouring  matter  of  the  cotton  from  the  action  of 
the  chlorine  used  in  the  latter  stages  of  bleaching. 
Some  proportion  of  the  waxy  and  oily  matter  is 
removed  during  the  process  of  spinning  and  a 
further  quantity  when  the  cloth  is  treated  with 
boiling  water.  The  heat  causes  the  wax  to  melt, 
and  it  is  carried  away  mechanically. 


Cotton — Natural  Moisture  in. 


469 


Natural  Moisture. — The  amount  of  natural 
moisture  in  cotton  is  eight  per  cent.  That  is,  in 
every  roo  parts  by  weight  of  cotton  there  are  eight 
parts  by  weight  of  water.  If  raw  cotton  or 
unbleached  cotton  yarn  be  dried  it  very  quickly 
absorbs  moisture  on  exposure  to  the  atmosphere. 
This  is  due  to  the  presence  of  deliquescent  salts  in 
the  mineral  matter  contained  in  the  fibre.  It  is 
a  well-known  fact  that  cotton  which  has  been 
boiled  with  caustic  soda  and  afterwards  " soured"  in 
hydrochloric  acid  does  not  absorb  water  to  the  same 
extent  as  raw  cotton,  or  as  cotton  yarn  which  has  been 
simply  dried.  Cloth  which  has  been  bleached  loses 
a  great  amount  of  its  hygroscopic  nature.  The 
bleaching  operations  remove  the  deliquescent  salts, 
and  thus  prevent  to  a  certain  extent  the  cloth  taking 
up  moisture  when  it  is  exposed  to  the  atmosphere- 
To  such  an  extent  does  bleached  cloth  lose  its  power  of 
rapidly  absorbing  moisture  that  it  is  essential  to  pass 
it  over  a  damping  machine  before  it  can  be  starched 
and  "finished." 

In  the  process  of  spinning  a  large  proportion 
of  the  natural  moisture  is  removed.  In  order  to  re- 
gain the  weight  which  has  been  lost  it  is  customary 
for  the  spinner  to  moisten,  or,  as  it  is  called,  to  "  con- 
dition," the  yarn  before  it  is  sent  to  the  manufacturer. 
If  this  "conditioning"  were  carried  out  simply  for 
the  purpose  of  replacing  moisture  which  had  been 
removed  in  the  spinning  process  there  would  be  no 


470      The  Chemistry  and  Practice  of  Sizing. 

objection  to  it,  but  unfortunately  it  is  the  custom 
of  some  spinners  to  add  as  much  water  as  they  can 
with  the  object  of  selling  water  in  place  of  cotton 
yarn.  From  this  it  will  be  seen  that  cotton  yarn, 
as  received  from  the  spinner,  may  contain  anything 
from  8  to  15  or  16  per  cent,  of  water.  Anything 
above  eight  per  cent,  is  water  which  has  been  added 
after  the  cotton  has  been  spun  into  yarn.  It 
would  be  to  the  advantage  of  the  manufacturer 
if  he  would  regularly  test  the  cops  for  the  amount 
of  water  contained  in  them.  All  added  water  is 
lost  when  the  yarn  is  passed  over  the  drying 
cylinder  of  the  tape  frame,  consequently  the  manu- 
facturer pays  for  something  which  does  not  appear 
in  the  woven  cloth. 

It  has  become  the  practice  in  recent  years  for 
certain  spinners  to  treat  their  yarns  with  deliquescent 
chemicals,  such  as  the  chlorides  of  magnesium,  cal- 
cium and  zinc,  for  the  purpose  of  increasing  its  powers 
of  absorbing  moisture.  These  chemicals  also  assist 
in  preventing  the  moisture  drying  out.  This  practice 
cannot  be  too  strongly  condemned  as  it  is  certain  to 
cause  serious  damage  to  cloth  which  has  to  be 
singed  previous  to  bleaching.  Not  only  is  there  a 
liability  to  damage  if  the  cloth  has  to  be  bleached, 
but  there  is  also  the  loss  to  the  manufacturer  through 
shortage  in  length.  The  authors  know  of  many 
instances  where  the  above  chemicals  have  been  used 
by  the  spinner  and  where  serious  loss  has  been 


" Overdarnping"  Cotton  Yarn, 


471 


caused  to  the  manufacturers.  In  many  cases  suspicion 
has  been  aroused  by  the  yarn  sticking  and  breaking 
during  winding.  The  operatives  have  complained 
about  the  quality  of  the  yarn,  whereas  the  cause  of 
complaint  has  been  the  presence  of  the  substances 
just  mentioned. 

The  over-damping  of  cotton  yarn  has  been 
carried  to  such  an  extent  that  mildew  has  actually 
developed  on  the  "cops"  before  they  have  been 
woven  into  cloth.  To  prevent  this  evidence  of 
over-damping  being  shown  spinners  have  employed 
crude  carbolic  acid  and  other  antiseptics.  Where 
crude  carbolic  acid  has  been  used  stains  have 
actually  shown  on  the  "cops"  where  they  have  come 
in  contact  with  the  "damping"  cloths  through  the 
presence  of  tar  oil  in  the  carbolic  acid. 

There  is  another  serious  aspect  to  this  question 
of  "over-damp"  yarn,  and  that  is  its  liability  to 
cause  mildew  when  it  is  woven  into  cloth.  This 
applies  more  particularly  to  weft  than  to  warp, 
because  the  warp  yarn  is  boiled  during  sizing,  and 
in  this  way  prevents  further  development  of  the 
mildew,  It  will  be  readily  understood  that  if  mildew 
is  already  present  in  the  weft  and  is  woven  into 
a  "pure"  sized  cloth  in  which  chloride  of  zinc  is 
not  employed  in  the  size,  mildew  is  certain  to 
develop  and  spread  through  the  whole  cloth.  The 
weft  may  not  show  any  actual  signs  of  mildew  when 
casually   examined,  and   no  apparent   damage  is 


472      The  Chemistry  and  Practice  of  Sizing. 

shown  until  it  comes  in  contact  with  the  starchy 
matter  on  the  warp.  The  starch  will  form  an  excellent 
medium  for  it  to  develop  and  spread,  and  the  cloth 
will  be  entirely  ruined.  This  effect  may  not  be 
produced  for  some  time  after  it  is  woven,  and  then  it 
will  be  almost  impossible  to  prove  how  the  damage 
has  occurred.  Generally  the  taper  is  blamed  for 
not  drying  the  yarn  sufficiently. 

If  manufacturers  would  unite  and  make  a  firm 
stand  against  this  practice  of  over-damping  yarns  it 
would  be  greatly  to  their  advantage.  If  it  were 
made  a  condition  that  all  excess  of  moisture  over 
8*5  per  cent,  would  be  claimed  on,  by  deducting 
from  the  spinners'  account,  the  practice  would  very 
quickly  cease. 

PHYSICAL  EXAMINATION  OF 
TEXTILE  FIBRES. 

It  is  necessary  to  employ  the  microscope  in  order 
to  determine  the  nature  of  the  fibre  from  which  a 
yarn  has  been  spun.  Chemical  tests  may  be 
employed  also,  but  the  microscopic  examination  is 
generally  the  more  trustworthy. 

VEGETABLE  FIBRES. 
Cotton,  Flax,  and  Hemp. 

The  fibres  of  the  above  substances  are  shown  to 
differ  considerably  in  structure  when  viewed  with 
the  aid  of  the  microscope. 


Examination  of  Textile  Fibres, 


473 


Cotton. — Under  the  microscope,  cotton  fibre 
appears  as  a  wide  band,  generally  twisted  as  shown 
on  plates  xv.  and  xva. 

Flax. — Linen. — Flax  is  composed  of  the  bast 
fibres  of  the  stem  of  the  flax  plant  (Linum 
usitatissimum).  The  fibres  consist  of  chemically 
pure  cellulose,  and  are  of  regular  thickness.  The 
cells  are  built  up  in  a  regular  manner,  cylindrical  in 
shape,  having  the  nodes  arranged  at  regular  intervals. 
An  illustration  of  magnified  linen  fibres  is  shown  on 
plate  xvi. 

Hemp.  —  Hemp  is  composed  of  the  bast  fibres  of 
the  stem  of  the  hemp  plant  ( Cannabis  sativa).  The 
cells  are  very  irregular  in  form,  and  do  not  possess 
nodes  as  in  the  case  of  flax.  The  cell  walls  are  not  of 
such  constant  thickness  as  flax,  and  the  ends  of  the 
fibres  are  blunt,  having  thick  walls,  frequently 
branching  laterally.  An  illustration  of  magnified 
hemp  fibres  is  shown  on  plate  xvia. 

Hemp  is  used  principally  for  the  manufacture  of 
ropes,  sacking,  canvas,  etc.  It  is  eminently  suited 
for  this  purpose  on  account  of  its  strength.  It  does 
not  readily  rot  when  in  contact  with  water.  Hemp 
is  rarely  bleached,  for  although  this  is  possible,  the 
coarseness  of  the  material  renders  it  unsuitable  for 
clothing-. 

Jute. — Jute  is  obtained  from  the  bast  fibres  of 
the  stems  of  several  kinds  of  Corchorus,  especially 
Cor  chorus  capsular  is  and  Corchorus  olitorius.  The 


474       The  Chemistry  and  Practice  of  Sizing. 


fibre  has  a  whitish  yellow  colour  but  turns  brown  on 
ageing.  The  cell  walls  are  irregular  in  thickness  and 
the  internal  and  exterior  border  lines  are  not  parallel. 
An  illustration  of  magnified  jute  fibres  is  shown  on 
plate  xvii. 

ANIMAL  FIBRES. 
Wool  and  Silk. 

Wool. — Wool  is  obtained  principally  from  the 
hair  of  the  sheep,  the  goat,  and  the  camel.  The 
appearance  of  wrool  under  the  microscope  is  shown 
on  plate  xviia% 

Wool  differs  very  considerably  in  chemical  com- 
position from  cotton  and  flax.  It  consists  of  horny 
matter  (keratin),  carbon,  hydrogen,  oxygen,  nitrogen, 
and  sulphur.  This  composition  is  most  strikingly 
noticed  when  wool  is  burnt.  The  peculiarly  dis- 
agreeable smell  of  burning  horn  is  given  off.  Boiling 
caustic  soda  or  caustic  potash  solutions  readily 
dissolve  wool.  If  acetic  acid  in  excess  be  added  to  the 
solution  obtained,  sulphuretted  hydrogen  is  given  off. 

Wool  is  very  hygroscopic.  The  amount  of 
moisture  found  in  woven  cloth  varies  from  15  to 
i8'25  per  cent,  and  this  amount  is  allowed  officially 
on  the  Continent  for  army  clothing  contracts, 

Silk. — This  fibre  is  obtained  from  the  larvee  of 
various  insects,  and  it  is  that  with  which  they 
surround  themselves  before  entering  the  pupal 
stage.      The  cocoon,  or  envelope  thread,  is  the 


Chemical  Examination  of  Fibres,  475 


result  of  the  hardening  of  the  fluid  ejected  from 
the  serecteria  of  the  larva. 

Silk  exhibits  no  definite  structure,  but  consists 
of  cylindrical  or  flattened,  sometimes  helical,  compact 
threads.  It  is  chemically  composed  of  silk  gelatin, 
silk  fibre,  with  fat,  resin,  colouring  matter,  and 
mineral  substances.  When  viewed  under  the  micro- 
scope silk  appears  as  a  smooth  cylinder  without  any 
contents. 

CHEMICAL  EXAMINATION  OF 
TEXTILE  FIBRES. 

Vegetable  fibres  may  be  readily  distinguished 
from  animal  fibres  by  burning. 

Animal  Fibres,  such  as  wool  and  silk,  give  off 
the  smell  of  burnt  horn  They  do  not  fire  like 
vegetable  fibres,  but  cease  to  burn  when  removed 
from  the  flame,  and  the  burnt  portion  curls  up, 
forming  a  hard  cinder  at  the  end  of  the  thread. 

Vegetable  Fibres,  on  the  other  hand,  give 
off  a  slight  smell  of  burnt  wood  when  ignited, 
They  burn  away  very  rapidly  with  a  flash, 
leaving  no  hard  cinder,  but  a  white  or  grey 
ash  only. 

The  above  test  broadly  distinguishes  vegetable 
from  animal  fibres,  but  further  chemical  examination 
is  necessary  to  distinguish  mixtures  of  any  of  them 
when  woven  into  cloth. 


476       The  Chemistry  and  Practice  of  Sizing. 


The  following  solutions  will  be  required  for 
making  the  chemical  tests. : — 

1.  Ammoniacal  Copper  Oxide  Solution. 

2.  Ammoniacal  Nickel  Oxide  Solution. 

3.  Chloride  of  Zinc  Solution. 

4.  Iodine  Solution. 

5.  Fuchsine  Solution. 

6.  Nitric  Acid,  Commercial. 

7.  Sulphuric  Acid,  58°B  strength  =  134°  !". 

8.  Hydrochloric  Acid,  3  per  cent. 

9.  Caustic  Soda  Solution,  o'i  per  cent. 

10.  Caustic  Potash  Solution,  10  per  cent. 

11.  Caustic  Soda  Solution,  sp.  gr.  1*05. 

SEPARATION  OF  WOOL  AND  COTTON 
IN  A  MIXED  FABRIC. 

A  weighed  portion  of  the  fabric  is  dried  in  the 
water  oven  until  all  moisture  is  driven  off.  It  is 
then  weighed  in  a  stoppered  glass  tube,  as  described 
on  page  492,  and  the  amount  of  loss  calculated  to  a 
percentage. 

The  dried  cloth,  the  weight  of  which  is  known 
from  the  last  operation,  is  boiled,  first  with  very 
dilute  caustic  soda  solution  and  afterwards  with  very 
dilute  hydrochloric  acid,  in  order  to  remove  the 
dressing  and  colour.  Care  must  be  taken  that  the 
liquors  are  not  allowed  to  become  concentrated,  and 
fresh  water  should  be  added  periodically  to  make  up 
for  the  loss  caused  by  evaporation.  After  the  treat- 
ment with  acid  and  alkali  the  fabric  is  boiled  in 
clean  water  for  an  hour  and  afterwards  well  washed. 


Chemical  Examination  of  Fibres.  477 


After  washing,  it  should  be  dried  and  weighed  in 
the  weighing  bottle.  The  loss  in  weight  represents 
dressing  and  colouring  matter.  The  amount  of  the 
dressing,  etc.,  is  then  calculated  to  a  percentage  of 
the  original  weight  of  cloth  taken. 

If  the  whole  of  the  colour  be  not  removed  by 
the  foregoing  treatment,  the  dried  fabric  should  be 
treated  writh  ether  in  the  Soxhlet's  tube,  as  described 
on  page  493. 

After  the  dressing  and  colour  have  been  removed 
the  dried  cloth  should  be  immersed  in  ammoniacal 
copper  oxide  solution  for  twenty  minutes.  This 
dissolves  the  cotton  fibre.  Water  should  then  be 
added  and  the  residue  filtered  off.  This  residue 
should  be  thoroughly  washed,  dried,  and  weighed. 
The  weight  found  is  the  amount  of  d7y  wool  in  the 
mixed  fabric,  and  to  this  should  be  added  the  amount 
of  water  natural  to  it,  and  this  weight  calculated  to 
a  percentage  of  the  original  cloth  taken. 

To  determine  the  percentage  of  cotton  present 
a  second  portion  of  the  fabric  is  freed  from  dressing 
and  colour,  and  treated  as  follows : — 

The  fabric  should  be  boiled  for  two  hours  in  a 
solution  of  caustic  potash,  8°B.  During  the  boiling 
operation,  water  should  be  added  to  make  up  for  loss 
due  to  evaporation.  The  wool  is  dissolved  out  by 
this  treatment.  The  cloth  is  then  well  washed  with 
water,  rinsed  in  dilute  hydrochloric  acid,  washed 
again  in  water,  and  finally  re-dried  until  the  weight 


478      The  Chemistry  and  Practice  of  Sizing. 

is  constant.  To  the  weight  of  dry  cotton  the  amount 
of  natural  moisture  (8  per  cent,  of  the  natural 
cotton),  should  be  added,  and  the  amount  of  natural 
mineral  matter  (i  per  cent.),  and  the  total  amount  of 
natural  cotton  should  then  be  calculated  to  a  percen  - 
tage of  the  original  cloth  operated  upon.  The 
amount  of  moisture  natural  to  the  cotton  is 
deducted  from  the  total  moisture  found. 

The  analysis  will  now  read  as  follows: — 

Per  Cent. 

Natural  Cotton,  including  moisture  

Moisture,  less  moisture  due  to  cotton  

Dry  Wool  

Dressing  

The  moisture  found  in  wool,  as  previously  stated, 
is  15  to  18*25  per  cent.;  therefore  about  18  per 
cent,  should  be  added  to  the  percentage  of  dry  wool. 
This  amount  of  moisture  should  be  deducted  from 
the  total  moisture  found.  If  this  18  per  cent,  does  not 
include  all  the  moisture  found  in  the  fabric  (except 
that  which  is  due  to  cotton),  the  balance  is  excess 
moisture,  due  either  to  the  dressing  or  to  added 
water.    The  corrected  analysis  will  then  read: — 

Fer  Cent. 

Natural  Cotton,  including  moisture... 
Natural  Wool,         do.  do. 

Dressing  

Excess  Moisture   


Separation  of  Cotton  and  Linen.  479 


DETECTION    AND  SEPARATION 
OF  COTTON  AND  LINEN. 

The  fabric,  if  white,  should  be  treated  with 
alcoholic  fuchsine  solution  (1  per  cent,  strength). 
It  is  afterwards  washed  with  clean  water  until 
the  colour  ceases  to  run,  and  then  steeped  in 
solution  of  ammonia  for  a  few  minutes.  Linen  is 
dyed  a  rose  colour,  whilst  cotton  remains  uncoloured. 
(This  test  is  reliable  only  if  the  fabric  be  free  from 
starch.  If  starch  has  been  used  in  the  "finishing" 
process  it  may  be  removed  by  treating  the  cloth 
with  a  solution  of  malt,  as  described  on  page  47. 
The  diastase  in  the  malt  renders  the  starch  soluble, 
and  it  may  then  be  removed  by  boiling  in  water). 

Strong  caustic  potash  solution  imparts  a  very 
slight  yellowish  tint  to  cotton,  whereas  linen  is  dyed 
a  deep  yellow.  This  alkali  may  therefore  be  used 
as  a  test  for  detecting  cotton  in  linen. 

Where  it  is  necessary  to  get  out  the  proportion 
of  cotton  and  linen  in  a  fabric,  the  following 
method  of  procedure  may  be  adopted  : — The  per- 
centages of  dressing  and  moisture,  in  a  carefully 
weighed  portion  of  the  cloth,  should  be  determined 
by  the  methods  described  on  pages  49 1  and  492,  The 
cloth  is  then  placed  in  strong  sulphuric  acid  (66° B)  for 
two  minutes,  rinsed  out  well  with  water,  and  rubbed 
between  the  fingers.  It  is  afterwards  neutralised  by 
soaking  in  a  dilute  solution  of  carbonate  of  sodium, 
and  then  in  ammonia.    The  fabric  is  further  well 


480      The  Chemist7y  and  Practice  of  Sizing. 

washed  in  water  and  dried.  Linen  fibre  is  not 
destroyed  by  this  treatment;  cotton  fibre  is  dissolved. 
The  amount  of  linen  found  should  be  calculated  to  a 
percentage. 

SEPARATION  OF  SILK  AND  COTTON. 

The  dressing  and  dye  having  been  removed,  as 
previously  described,  the  fabric  is  treated  with 
ammoniacal  nickel  oxide,  which  dissolves  out  the 
silk.  A  quantitative  estimation  may  be  made  by 
getting  out  the  percentage  of  moisture,  dressing, 
and  total  fibre,  as  described  on  page  491  et  seq. 

Silk  is  dissolved  by  a  strong  boiling  solution  of 
chloride  of  zinc. 

SEPARATION  OF  SILK  AND  WOOL. 

These  fibres  may  be  estimated  in  a  mixed  fabric 
by  boiling  a  weighed  portion  in  hydrochloric  acid. 
Silk  is  readily  dissolved  by  this  treatment ;  wool 
simply  swells  up. 


Analysis  of  Sized  Grey  Cloth.  481 


Chapter  XIII. 


The  A  nalysis  of  Sized  Grey  Cloth. 


MANUFACTURER  very  often  requires  to 


l  \  know  the  amount  and  general  composition 
of  the  size  contained  in  a  piece  of  cotton  cloth. 
This  information  may  be  required  in  order  to  match 
the  cloth,  or  it  may  be  required  in  order  to  deter- 
mine the  cause  of  some  damage,  such  as  the 
formation  of  mildew  or  iron  stains.  Where  it  is 
required  to  match  the  cloth,  it  is  possible  for  the 
manufacturer  to  make  an  analysis  sufficient  for  the 
purpose,  providing  he  has  the  necessary  facilities. 
But  when  damage  has  occurred  it  will  not  be  advis- 
able for  him  to  attempt  to  solve  the  difficulty,  even 
if  he  possesses  the  necessary  qualifications.  At  the 
same  time  nothing  will  be  lost  by  giving  a  full 
description  of  the  processess  involved  in  making 
a  cloth  analysis.  With  this  object  in  view  the 
writer  intends  to  first  describe  the  method  of 
determining  the  percentages  of  cotton  fibre 
and  size  in  a  sample  of  cloth,  and  the 
method     of    determining     the     nature     of  the 


E2 


482      The  Chemistry  and  Practice  of  Sizing. 

constituents  of  the  size,  and  afterwards  the  method 
of  determining  the  proportions  of  the  various 
ingredients  which  may  be  found  present. 

1st.— QUALITATIVE  ANALYSIS. 

A  portion  of  the  cloth  is  steeped  in  cold  distilled 
water  for  twelve  hours.  The  liquid  is  afterwards 
filtered  off,  and  examined  as  follows  : — 

(a)  Acidity  or  Alkalinity.  —  These  conditions 
should  be  tested  for  by  means  of  litmus  paper,  as 
described  on  page  34. 

(b)  Chlorides  and  Sulphates. — The  presence 
of  chlorides  and  sulphates  should  be  determined  as 
follows : — 

(1)  Chlorides. — To  a  portion  of  the  original 
solution  a  few  drops  of  the  nitric  acid  and  nitrate  of 
silver  solution  should  be  added.  The  formation  of 
a  white  curdy- precipitate  indicates  chlorides.  This 
precipitate  should  be  insoluble  in  strong  nitric  acid, 
but  soluble  in  an  excess  of  ammonia. 

(2)  Sulphates. — To  another  portion  of  the 
original  solution  a  few7  drops  of  hydrochloric  acid 
and  chloride  of  barium  solution  should  be  added. 
The  formation  of  a  heavy  white  precipitate  indicates 
sulphates.  If  a  heavy  precipitate  be  obtained  by 
the  above  test,  the  presence  of  Epsom  salts  or 
Glauber's  salts  is  indicated ;  the  probability  being 
that  it  is  Epsom  salts. 


Analysis  of  Grey  Cloth.  483 


(c)  Salts  of  Zinc,  Calcium,  and  Magnesium, 
should  be  tested  for  as  follows: — 

(1)  Zinc. — To  a  portion  of  the  filtered  solution 
a  few  drops  of  solution  of  ammonia,  chloride  of 
ammonium,  and  sulphide  of  ammonium,  should  be 
added.  The  formation  of  a  white  precipitate 
(sulphide  of  zinc)  indicates  the  presence  of  zinc. 
Sometimes  this  precipitate  is  dark  through  the 
presence  of  traces  of  iron  salts. 

If  zinc  be  present,  another  portion  of  the  original 
solution  is  treated  as  follows  : — 

(2)  Calcium  and  Magnesium. — Solutions  of 
ammonia  and  chloride  of  ammonium  should  be 
added  in  access.  The  excess  of  ammonia  dissolves 
the  zinc  (wThich  is  first  precipitated  as  hydrate  of 
zinc),  whilst  the  excess  of  chloride  of  ammonium 
prevents  the  precipitation  of  magnesium  along  with 
the  calcium  in  the  next  test. 

Calcium. — To  the  above  prepared  solution  a 
solution  of  oxalate  of  ammonium,  in  slight  excess, 
is  added.  Calcium,  if  present,  is  precipitated  as 
oxalate  of  calcium.  If  a  white  precipitate  be  formed 
it  is  filtered  off,  and  the  filtered  liquid  tested  for 
magnesium  as  follows: — 

Magnesium, — A  solution  of  phosphate  of  am- 
monium should  be  added  to  the  solution  from  the 
calcium  precipitate.  The  immediate  formation  of 
white  granular  precipitate  (magnesium  ammonium 
phosphate),  indicates  magnesium. 


484      The  Chemistry  and  Practice  of  Sizing. 

In  all  cases  an  excess  of  each  reagent  must  be 
added  in  order  to  prevent  a  base  being  carried 
forward  through  incomplete  precipitation.  This 
may  be  easily  avoided  if  the  mixture  be  filtered  and 
a  little  more  of  the  reagent  added.  If  no  further 
precipitation  takes  place  the  whole  of  the  base  in 
question  has  been  removed. 

(d)  Dextrin. — This  substance  may  be  present 
as  an  ingredient  of  the  size,  or  it  may  be  present  on 
account  of  the  use  of  wheaten  flour  of  which  it  is  a 
constituent.  Dextrin  is  soluble  in  cold  water,  and 
it  may  be  detected  by  means  of  iodine  solution,  as 
described  on  page  53. 

(e)  Starch  and  China  Clay. — The  residue 
on  the  filter  paper,  through  which  the  original 
solution  was  filtered,  will  contain  the  starch  and 
China  clay,  if  present.  A  portion  of  this  residue 
should  be  tested  for  starch  with  iodine  solution,  as 
described  on  page  36.  Another  portion  of  the 
residue  should  be  examined  under  the  microscope. 
Insoluble  mineral  matter  such  as  clay  will  be  at 
once  detected,  and  very  often  a  number  of  unbroken 
granules  of  starch  will  be  found,  showing  what 
particular  starch  has  been  used  in  the  size. 

The  foregoing  tests  will  give  a  general  indication 
of  the  composition  of  the  size.  It  will  then  be 
necessary  to  determine  the  proportions  of  cotton 
fibre  and  size  in  the  cloth,  together  with  the  percentage 
of  mineral  matter  present.     The  simplest  method 


The  Cloth  Quadrant.  485 

of  determining  the  percentages  of  cotton  fibre  and 
size  is  carried  out  by  means  of  the  cloth  quadrant 
which  is  shown  below. 


The  Cloth  Quadrant. 


This  most  useful  instrument  is  used  as  follows  : — 
A  piece  of  cloth  exactly  one-tenth  of  a  yard  square 
(a  templet  is  sold  with  each  quadrant  which  is  exactly 
one-tenth  of  a  yard  square)  is  cut  from  the  middle 
of  the  sample  undergoing  examination.  A 
very  sharp  knife  is  used  for  this  purpose,  so  that 


486      The  Chemistry  and  Practice  of  Sizing. 

the  cloth  may  be  cut  perfectly  clean.  Any  loose 
threads  of  warp  and  weft  should  be  pulled  out, 
passed  through  a  hole  made  in  the  side  of  the  cloth, 
and  tied.  The  cloth  is  then  put  on  the  hook  of  the 
quadrant  and  the  weight  in  pounds  noted.  The 
weight  shown  is  the  equivalent  of  a  piece  of  cloth 
100  yards  long  and  one  yard  wide. 

The  cloth  should  then  be  chemically  washed, 
and  afterwards  dried  until  it  ceases  to  lose  weight. 
It  is  then  again  weighed  on  the  quadrant.  The 
method  of  chemically  washing  is  described  in  detail 
on  page  491.  The  result  of  the  second  weighing 
gives  the  weight  in  pounds  of  pure  dry  cotton  fibre. 
To  this  should  be  added  eight  per  cent,  for  the 
moisture  natural  to  cotton  and  one  per  cent,  for 
the  natural  mineral  matter  removed  by  washing. 
After  these  additions  have  been  made  the  weight  is 
calculated  to  a  percentage  of  the  original  cloth 
taken  ;  the  loss  being  size,  and  moisture  due  to  the  size. 

The  amount  of  weft  present  in  the  cloth  may  be 
obtained  by  the  aid  of  the  quadrant  as  follows: — 
The  sample  submitted,  the  actual  width  of  which 
must  be  known,  should  be  more  than  18  inches  wide 
in  order  that  threads  of  weft  exactly  18  inches  long 
may  be  obtained  from  it. 

A  measure  exactly  18  inches  long  is  sold  with  the 
quadrant. 

The  cloth  is  straightened  out  and  the  measure 
laid  upon  it.     A  portion   18  inches  wide  is  cut 


Determination  of  the  "Counts"  of  Yarn.  487 

by  passing  a  sharp  knife  across  the  ends  of  the 
measure.  This  piece  is  then  torn  weft  way  to  get 
a  straight  edge  and  afterwards  weft  threads  are 
pulled  out  until  8  threads  are  obtained.  This  weft, 
a  total  of  4  yards,  is  hung  on  the  hook  of  the 
quadrant  which  registers  the  "counts." 

Another  8  threads  should  then  be  taken  from 
the  cloth,  and  after  the  "counts"  have  been  ascertained, 
the  whole  16  threads  should  be  hung"  on  the  hook 
and  the  number  shown  on  the  quadrant  multiplied 
by  2.  These  operations  should  be  repeated  on 
several  portions  of  the  cloth  in  order  to  get  a  fair 
average  of  the  ''counts"  of  weft  in  the  cloth. 

In  all  cases  the  "counts"  as  shown  by  the  quad- 
rant are  slightly  heavier  than  the  actual  "counts" 
used  in  the  cloth.  This  is  due  to  the  interlacing  of 
the  weft  with  the  warp.  It  will  easily  be  seen  that 
there  will  be  more  than  18  inches  of  yarn  in  the 
measured  18  inches  of  cloth.  The  exact  determin- 
ation of  the  counts  of  weft  requires  considerable 
experience.  For  one  thing  it  is  necessary  to  take  into 
account  the  "reed"  and  "pick,"  because  the  increase 
in  the  number  of  threads  per  inch  will  increase  the 
length  of  actual  yarn  in  the  measured  cloth. 

After  obtaining  the  percentage  of  cotton  writh  its 
natural  moisture,  the  "counts"  of  weft,  and  the 
"reed"  and  "pick,"  a  calculation  will  enable  the 
manufacturer  to  determine  the  percentage  and 
"counts"  of  twist.      From  these  data  he  will  be 


488      The  Chemistry  and  Practice  of  Sizing, 


able  to  calculate  the  percentage  of  size  on  the 
twist.    An  actual  example  is  given  below : — 

For  100  Yards,  36  Inches  Wide,  64  x  64. 

A  Sample  of  cloth  weighs    23'75  lbs. 

The  weft  indicates  32's  on  the  quadrant. 

After  washing  out  the  size,  drying,  and 
adding  9%  for  natural  moisture  and  mineral 
matter  the  cloth  weighs   17*00  lbs. 

Weight  of  size  and  moisture...   675  lbs. 

Total  weight  of  yarn   i7'oo  lbs. 

Total  weight  of  size   675  lbs. 

2375  lbs. 

The  weight  of  weft  is  obtained  by  the  following 
calculation : — 

38    X    64    X  IOO 

 o  —  —  9*°S  lbs.  weft. 

840  x  32  y  0 

Total  weight  of  yarn   17  00  lbs. 

Total  weight  of  weft   9*05  lbs. 

Total  weight  of  twist     795  lbs. 

The  "counts"  of  twist  may  be  determined  by 
the  following  calculation  : — 

36  x  64  x  ic6 

— o  Z7~z~.         =  36*5  "counts." 

840  x  7  95         ^  D 

Total  weight  of  twist    7*95  lbs. 

Total  weight  of  size   675  lbs. 

Percentage  of  size  on  twist  85*0  percent. 


Determination  of  the  "Counts"  of  Yarn.  489 

It  will  be  seen  that  2  inches  have  been  added  to 
the  36  inches  for  the  weft,  and  6  yards  to  the  100 
yards  for  the  twist.  This  is  to  allow  for  the 
increased  length  due  to  the  interlacing  of  the  yarns} 
or,  as  it  is  commonly  termed,  "the  contraction  in 
the  cloth." 

In  actual  sizing  from  such  data  allowance  must 
be  made  for  the  loss  of  size  occuring  between 
tapeing  and  the  woven  cloth. 

The  "counts"  of  the  twist  and  the  percentage  of 
size  present  on  it  may  also  be  determined  as  follows: 
Twist  threads,  to  the  number  of  210  each  18  inches 
in  length  (105  yards  or  ^  of  the  length  of  a  hank  of 
yarn),  are  carefully  pulled  from  the  cloth,  taking 
care  to  rub  off  as  little  size  as  possible.  The 
weight  \w  grains  of  these  threads  is  ascertained  by 
means  of  the  balance,  using  the  weighing  tube 
described  on  page  22.  The  threads  are  then 
chemically  washed,  as  described  on  page  491,  and 
afterwards  dried.  After  drying  they  are  again 
weighed.  The  weight  found  is  carefully  noted,  and 
to  this  weight  9  per  cent,  for  natural  moisture  and 
mineral  matter  should  be  added.  This  gives  the 
weight  of  actual  twist  present  in  the  210  threads 
taken,  the  balance  being  size.  In  order  to  ascertain 
the  "counts"  of  twist,  the  corrected  weight,  ingrains, 
of  the  210  threads  is  multiplied  by  8.  This  gives 
the  weight  for  840  yards  =  1  hank.  As  there  are 
7,000  grains  in  1  pound  it  will  be  necessary  to  divide 


490      The  Chemistry  and  Practice  of  Sizing. 

7,000  by  the  weight,  in  grains,  of  the  hank.  This 
will  give  the  "counts." 

After  getting  out  the  ''counts"  the  percentage 
of  size  on  the  twist  may  be  calculated.  The  weight 
of  the  210  threads,  after  chemically  washing  and 
drying,  etc.,  and  correcting  for  natural  moisture 
and  ash,  should  be  calculated  to  a  percentage. 
Thus,  if  50  per  cent,  of  cotton  and  50  per  cent, 
of  size  be  found,  the  twist  would  have  100  per 
cent,  of  size  on  it. 

An  example  will  make  the  foregoing  description 
more  clear : — 

Calculation  for  "Counts"  of  Twist. 

210  twist  threads  weighed    53'88  grains. 

After  chemically  washing,  and  drying,  and 
correcting  for  natural  moisture  and  ash, 
they  weighed     2  5*13  grains. 

Balance  =  weight  of  size  on  210  threads,  2875  grains- 

25"  1 3  grains  X  8  =  201*04  =  weight  of  1  hank,  840  yards. 

This  divided  into  7,000  grains  =  1  pound  gives  34's  "counts" 
of  twist  approximately. 

Calculation  for  Percentage  of  Size  on  Twist. 
2 5 "13  grains  =  2875  grains  of  size. 

therefore  =  2^  ^5  x — 1^?  _  per  cent,  of  size  on  twist. 

2513 

2nd. — QUANTITATIVE  ANALYSIS. 

When  it  is  desired  to  make  a  full  analysis  of  a 
sample  of  cloth,  the  following  procedure  should  be 
adopted : — 


Estimation  of  Total  Size. 


491 


Estimation  of^  Total  Size. — A  square  piece 
of  cloth,  10  or  15  grammes  in  weight,  is  cut,  not  torn, 
from  the  sample  to  be  analysed  in  such  a  way  as 
to  get  a  fair  average  piece.  Any  loose  threads 
should  be  pulled  out  carefully,  folded  up,  put  through 
a  hole  made  at  the  side  of  the  cloth,  and  tied.  This 
piece  should  be  most  carefully  weighed  in  the 
weighing  tube  and  the  weight  noted.  The  cloth  is 
then  thoroughly  washed  for  a  few  minutes  in  a 
stream  of  running  water  to  remove  as  much  size 
as  possible.  It  is  afterwards  placed  in  a  large 
enamelled  pan  or  evaporating  basin  containing  a 
1  per  cent,  solution  of  caustic  soda  and  boiled  for 
an  hour.  After  boiling,  the  cloth  is  taken  out  and 
thoroughly  washed  in  clean  running  water.  It  is 
then  boiled  in  a  1  per  cent,  solution  of  hydrochloric 
acid  for  one  hour.  Fresh  water  should  be  added  at 
regular  intervals  to  make  up  for  loss  by  evaporation. 
If  the  acid  liquor  becomes  concentrated  it  will 
tender  the  fibre. 

A  fter  boiling  in  acid  the  cloth  should  be  thoroughly 
washed  in  running  water  and  finally  boiled  for  an 
hour  in  clean  water,  after  which  it  is  washed  again, 
then  wrung  out  as  dry  as  possible,  and  placed  in  the 
steam  oven  to  dry. 

When  perfectly  dry  it  should  be  pushed  into 
the  stoppered  weighing  tube,  the  stopper  replaced, 
and  the  whole  allowed  to  cool  in  the  desiccator. 
It  is  then  weighed,    and   after    the  tare  of  the 


49 2       The  Chemistry  and  Practice  of  Sizing. 


tube  has  been  deducted  the  difference  will  be  the 
amount  of  pure  dry  cotton  fibre.  The  loss  in 
weight  represents  the  total  size,  with  the  moisture 
due  to  the  size,  and  the  moisture  and  mineral 
matter  natural  to  the  cotton. 

To  the  amount  of  dry  fibre  8  per  cent,  should  be 
added  for  natural  moisture  and  i  percent,  for  natural 
mineral  matter.  The  percentage  of  natural  cotton 
in  the  original  cloth  may  then  be  calculated.  This 
calculation  does  not  quite  give  an  accurate  result  as 
the  washing  processes  remove  a  certain  amount  of 
oily  and  waxy  matter  from  the  cotton  and  also  a 
certain  amount  of  fibre,  but  it  is  near  enough  for  all 
practical  purposes. 

The  reader  must  remember  that  in  every  ioo 
parts  of  natural  cotton  8  parts  are  moisture,  so  that 
8  must  be  added  to  every  92  parts  of  dried  cotton 
to  find  the  amount  of  natural  cotton.  The  following 
will  explain  the  calculation  more  clearly: — 

Weight  of  dry  fibre  X  8      amount  of  natural  moisture 
92  to  be  added  to  dried  fibre. 

Total  Moisture. — About  10  grammes  of  the 
cloth  should  be  carefully  weighed  in  the  weighing 
tube  and  dried  in  the  steam  oven  until  the  weight  is 
constant.  The  cloth  should  then  be  pushed  into  the 
tared  stoppered  glass  tube  whilst  hot,  and  weighed 
when  cold.  From  the  total  weight  deduct  the  tare 
of  the  tube.  The  balance  is  the  weight  of  the  dry 
fabric.     This  weight,  deducted  from  the  original 


Estimation  of  Fat  and  Wax.  493 


weight  of  the  cloth  taken,  gives  the  amount  of  loss 
which  is  due  to  moisture,  and  should  be  calculated 
to  a  percentage. 

The  above  estimation  should  be  made  very  care- 
fully as  the  question  of  damage  frequently  turns 
upon  the  amount  of  moisture  present  in  a  sample  of 
cotton  cloth.  Any  moisture  above  8  per  cent,  is 
expressed  as  excess  moisture. 

Estimation  of  Fatty  and  Waxy  Matters: — 
10  to  15  grammes  of  the  cloth  should  be  carefully 
weighed,  and  the  fat  or  wax  extracted  in  the 
Soxhlets  tube  by  means  of  ether  or  petroleum 
spirit.  An  illustration  of  the  Soxhlets  apparatus 
is  shown  on  page  494.  It  consists  of  a  Soxhlets 
tube  connected  with  a  strong  glass  flask  by 
means  of  a  good  cork.  The  upper  portion  of  the 
tube  is  connected  by  means  of  a  cork  with  an 
upright  condenser.  The  sample  of  cloth  is  placed 
in  the  Soxhlet  and  sufficient  ether  poured  into  the 
flask,  They  are  then  fitted  together  and  the  con- 
denser placed  in  position.  The  lower  tube  of  the 
condenser  is  attached  to  the  water  supply  by  means 
of  a  piece  of  rubber  tube.  The  upper  tube  is 
used  for  the  overflow.  The  supporting  stand  should 
be  sufficiently  high  to  allow  the  flask  to  be  placed 
in  the  bath  containing  water,  which  is  heated  by 
means  of  the  Bunsen's  flame. 

The  ether  distils  from  the  flask  and  passes  in 
the  form  of  vapour  through  the  Soxhlet  s  tube  into 


Soxhlet's  Fat  Extraction  Apparatus. 


Estimation  of  Fat  and  Wax. 


495 


the  condenser.  From  this  condenser  it  drops  back 
again  upon  the  cloth  in  the  Soxhlet's  tube  as  a  liquid. 
When  the  ether  reaches  a  certain  height  in  the  tube  it 
syphons  over  carrying  the  dissolved  fat  or  wax 
with  it. 

This  operation  is  repeated,  and,  as  the  distilled 
ether  is  continually  dissolving  fat  or  wax  from  the 
piece  of  cloth  and  passing  back  into  the  bottom 
flask,  this  will  eventually  become  charged  with  all 
the  fat  or  wax  previously  contained  in  the  cloth. 
The  apparatus  is  then  disconnected  and  the  solution 
of  fat  in  ether  is  afterwards  transferred  to  a  tared 
basin  which  is  heated  on  the  water  bath  until  the  ether 
is  driven  off,  It  is  then  transferred  to  the  drying  oven, 
and  dried  until  quite  free  from  any  trace  of  ether  or 
water.  After  drying  it  is  cooled,  weighed,  and  the 
weight  found  calculated  to  a  percentage  of  the  cloth 
taken. 

The  fat  may  be  examined  as  to  its  character, 
etc.,  and  certain  information  as  to  its  origin  obtained 
by  taking  the  melting  point.  Too  much  reliance 
must  not  be  placed  upon  the  indications  given  by  the 
melting  point  as  there  are  certain  small  quantities 
of  impurities  removed  from  the  cotton  itself  by  ether 
which  affect  this. 

Great  care  must  be  exercised  in  evaporating 
ether,  as  this  substance  is  very  inflammable. 

Mineral  Matter. — If  mineral  matter  has  been 
found  in  the  preliminary  analysis,  it  will  be  necessary 


496      The  Chemistry  and  Practice  of  Sizing. 

to  determine  its  amount  and  composition. 

About  10  grammes  of  the  cloth  should  be  care- 
fully weighed,  the  weight  noted,  and  the  cloth  burnt 
in  a  weighed  platinum  or  porcelain  crucible.  When 
the  whole  of  the  organic  matter  has  been  destroyed 
there  will  remain  a  white  or  grey  ash,  which  should 
be  carefully  weighed  and  the  weight  calculated  to  a 
percentage.  This  will  consist  of  the  China  clay  and 
the  other  mineral  substances  present. 

Before  the  percentage  of  China  clay  in  the 
percentage  of  total  ash  can  be  determined,  it  will 
be  necessary  to  ascertain  the  percentages  of  the 
other  mineral  substances  which  are  not  volatilised, 
such  as  the  chlorides  of  magnesium,  calcium,  and 
sodium,  and  the  sulphates  of  magnesium  and 
sodium. 

Chloride  of  magnesium  will  exist  in  the  ash  as 
oxide,  and  the  percentage  of  this  oxide  must  be 
deducted  from  the  percentage  of  ash. 

Chloride  of  calcium,  chloride  of  sodium  and  the 
sulphates  of  magnesium  and  sodium  will  exist  as 
such  in  the  ash  (but  without  their  natural  water),  and 
after  determining  their  percentages,  these  percentages 
should  be  deducted  from  the  percentage  of  ash. 

Cotton  ash,  to  the  amount  of  i  per  cent,  of  the 
cotton  fibre  found,  should  also  be  deducted  from  the 
total  percentage  of  ash. 

The  percentage  of  ash  then  remaining  after  these 
deductions  is  dry  China  clay,  and  to  this  should  be 


Analysis  of  Sized  Grey  Cloth,  497 


added  the  10  per  cent,  for  water  natural  to  ordinary 
China  Clay.  (N.B. —  Practically  the  whole  of  the 
chloride  of  zinc  will  be  removed  by  volatilisation 
during  the  incineration  of  the  cloth. 

Determination  of  Zinc,  Magnesium,  Calcium 
and  Sodium  Salts.  — 10  to  15  grammes  of  the  cloth 
should  be  carefully  weighed,  placed  in  a  dry  conical 
beaker  and  treated  as  follows: — About  250  c.c.  of 
distilled  water  should  be  roughly  measured,  and 
10  c.c.  of  strong  hydrochloric  acid  added.  From 
this  mixture  200  c.c.  are  taken  by  means  of  a  100 
c.c.  pipette,  and  run  into  the  beaker  containing  the 
cloth.  The  cloth  should  be  pressed  with  a  glass 
rod  in  order  to  allow  the  liquid  to  thoroughly 
saturate  it.  The  glass  rod  should  remain  in  the 
beaker  until  the  liquid  is  filtered  off.  The  beaker 
should  be  covered  over  with  a  watch  orlass  and  the 
cloth  should  be  allowed  to  digest  in  the  liquid  for  a 
few  hours,  with  occasional  stirring  and  pressing, 
after  which  it  is  filtered  off.  The  cloth  should  then 
be  wrung  out  over  the  filter  paper.  As  soon  as  the 
whole  of  the  solution  has  passed  through  the  filter 
paper  it  should  be  well  shaken  up.  100  c.c,  of  the 
filtered  solution  should  be  drawn  off  by  means  of  the 
pipette,  and  the  zinc,  calcium,  magnesium,  etc., 
determined  as  follows : — 

The  solution  is  first  boiled  with  a  few  drops  of 
nitric  acid,  and  afterwards  an  excess  of  ammonia 
and  chloride  of  ammonium  should  be  added.  Iron 

F2 


498       The  Chemistry  and  Practice  of  Sizing, 

(and  occasionally  alumina  from  the  China  clay)  is 
precipitated  if  present.  If  a  precipitate  be  formed 
it  must  be  filtered  off  and  washed.  The  washings 
should  be  collected  in  the  vessel  containing  the 
filtrate.  The  precipitate  is  re-dissolved  in  hydro- 
chloric acid,  and  re-precipitated  as  described  above, 
in  order  to  remove  any  trace  of  hydrate  of  zinc 
carried  down  with  the  iron  and  alumina  precipitates. 
The  filterate  and  washings  from  the  second  operation 
should  be  added  to  the  first  filterate.  A  solution  of 
sulphide  of  ammonium  should  then  be  added  in 
excess  to  the  cooled  filtrate  from  the  iron,  etc.,  and 
the  whole  set  on  one  side  for  a  few  hours.  The 
precipitate  of  sulphide  of  zinc  is  then  filtered  off 
through  a  filter  paper,  the  ash  of  which  is  known. 
This  precipitate  should  be  well  washed  with  a  mixture 
of  sulphide  of  ammonium  and  distilled  water.  The 
filtrate  and  the  washings  from  the  zinc  precipitate 
are  collected  in  a  beaker  and  tested  for  calcium  and 
magnesium  as  described  later.  The  zinc  precipitate 
is  dried  and  transferred  to  a  tared  crucible,  and 
ignited  for  some  time.  The  filter  paper  is  burnt  on 
the  lid  of  the  crucible,  ignited,  cooled,  treated  with 
a  drop  of  nitric  acid,  re-ignited,  and  weighed  along 
with  the  crucible.  The  oxide  of  zinc,  ZnO,  formed 
by  ignition,  is  weighed  and  calculated  to  chloride  of 
zinc. 

ZnO    =  ZnCL 
Zinc  Oxide    Zinc  Chloride 

81  136 


Analysis  of  Sized  Grey  Cloth.  499 


The  amount  of  chloride  of  zinc  found,  multiplied 
by  2,  gives  the  amount  present  in  the  cloth  taken, 
and  this  should  be  calculated  to  a  percentage. 

Calcium. — A  solution  of  oxalate  of  ammonium 
should  be  added  in  excess  to  the  filtrate  from  the 
zinc.  If  no  precipitate  be  formed  on  standing  a  few 
minutes  calcium  is  absent.  If  present  the  solution 
must  be  boiled.  It  is  better  to  avoid  boiling  if  calcium 
be  not  shown  in  the  cold  solution,  as  this  causes  a 
precipitation  of  sulphur  from  the  excess  of  sulphide 
of  ammonium  present. 

The  calcium  precipitate  should  be  filtered  off  and 
well  washed  with  distilled  water.  The  filtrate  and 
washings  should  be  reserved  for  the  magnesium 
determination. 

The  precipitate  of  oxalate  of  calcium  is  dried, 
transferred  to  a  weighed  crucible,  and  gently  ignited, 
thus  forming  carbonate  of  calcium.  It  is  then 
moistened  with  a  solution  of  pure  carbonate  of  am- 
monium, evaporated  to  dryness,  heated  until  no  more 
fumes  are  evolved,  and  weighed  as  carbonate  of 
calcium,  CaC03.    This  is  calculated  to  oxide,  CaO. 

CaC03     =  CaO 
100  56 

The  amount  of  oxide  multiplied  by  2  gives  the 
amount  present  in  the  cloth  taken  and  this  is 
calculated  to  a  percentage. 

The  calcium  may  have  existed  in  the  cloth  as 
chloride  or  as  sulphate  of  calcium,  or  both,  and  this 


500      The  Chemistry  and  Practice  of  Sizing. 

must  be  ascertained  when  making  up  the  results 
after  getting  out  the  percentage  of  sulphuric  acid  as 
(S03)  and  chlorine  (Cl2).  Whichever  salt  is  found 
it  will  be  necessary  to  deduct  the  percentage  from 
the  total  percentage  of  ash. 

The  filtrate  and  washings  from  the  calcium  pre- 
cipitate should  be  evaporated  down  to  about  30  c.c. 
The  sulphur,  which  is  precipitated  by  this  treatment, 
is  filtered  out  and  well  washed  with  boiling  distilled 
water  to  remove  every  trace  of  the  magnesium  or 
sodium  salts  which  may  be  present.  After  cooling 
the  filtrate  and  washings,  one-fourth  of  the  volume 
of  strong  ammonia,  and  an  excess  of  phosphate  of 
ammonium  should  be  added,  in  order  to  precipitate 
the  magnesium.  The  whole  should  be  set  aside  for 
some  hours.  Care  should  be  taken  not  to  touch  the 
sides  of  the  beaker  with  the  stirring  rod  other- 
wise particles  of  the  precipitate  will  adhere  so 
tenaciously  that  they  can  be  removed  only  with 
difficulty.  The  precipitate  should  be  collected  on  a 
filter  paper  and  thoroughly  washed  with  a  mixture 
of  distilled  water  and  ammonia.  The  filtrate  and 
washings  from  the  magnesium  are  mixed,  and  the 
amount  of  sodium  salts,  if  present,  determined  as 
described  later. 

The  magnesium  precipitate  is  dried,  and  trans- 
ferred to  a  weighed  platinum  crucible,  the  filter 
paper  is  burnt  on  the  lid,  and  the  ash  is  added  to  the 
contents  of  the  crucible.     The  whole  should  then 


Analysis  of  Sized  Grey  Cloth,  501 

be  strongly  ignited  for  some  time,  and  weighed  as 
pyrophosphate  of  magnesium  (Mg2P207).  It  some- 
times happens  that  even  after  prolonged  ignition  the 
magnesium  salt  remains  black.  Should  this  be  the 
case,  it  is,  after  cooling,  moistened  with  strong  nitric 
acid,  carefully  dried  and  re-ignited. 

The  pyrophosphate  of  magnesium  is  calculated 
to  oxide  (222  parts  by  weight  of  Mg2P207=:  80  parts 
by  weight  of  MgO). 

Mg2P207    =  2MgO 
222  80 

The  amount  of  oxide  found,  multiplied  by  2, 
gives  the  amount  of  oxide  present  in  the  cloth. 
This  is  calculated  to  a  percentage,  and  the  per- 
centage should  be  deducted  from  the  percentage  of 
total  ash.  From  the  percentage  of  oxide  of  mag- 
nesium, the  percentage  of  chloride  of  magnesium 
may  be  calculated.  Every  40  parts  of  oxide 
represent  95  parts  of  chloride. 

MgO  MgCL 
24+16      =       24  +  7 1 

40  95 

If  sulphates  have  been  found  in  the  preliminary 
tests,  the  magnesium  may  be  present  both  in  the 
form  of  sulphate  of  magnesium  and  chloride  of 
magnesium.  In  this  case  the  calculation  to  total 
chloride  will  have  to  be  omitted,  and  the  deduction 
from  the  percentage   of  ash  corrected  after  the 


502      The  Chemistry  and  Practice  of  Sizing. 

amount  of  magnesium  existing  as  sulphate  has  been 
ascertained.    The  correction  will  be  as  follows: — 

The  whole  of  the  percentage  of  sulphate  of 
magnesium  must  be  deducted  from  the  percentage 
of  ash,  and  the  percentage  of  chloride  of  magnesium 
then  calculated  back  to  oxide,  and  this  percentage 
of  oxide  also  deducted  from  the  ash. 

The  filtrate  and  washings  from  the  mag- 
nesium precipitate  should  be  evaporated  to  a 
small  bulk  and  the  sodium  salts  determined  as 
follows : — 

Determination  of  Sodium  Salts  as  Sul- 
phates,— The  sodium  may  have  existed  in  the  cloth 
as  chloride  of  sodium  or  sulphate  of  sodium,  or 
both.  An  excess  of  chloride  of  barium  solution 
should  be  added  to  the  solution  from  the  magnesium 
precipitate,  in  order  to  precipitate  phosphoric  acid. 

The  mixture  is  then  filtered  and  the  precipitate 
washed  with  distilled  water.  The  filtrate  and  wash- 
ings are  collected  in  a  beaker.  An  excess  of 
carbonate  of  ammonium  is  added  to  the  solution 
to  precipitate  the  excess  of  barium.  The  precipitate 
is  filtered  off  and  well  wrashed  with  distilled 
water.  The  filtrate  and  washings  are  transferred  to 
a  tared  porcelain  basin,  and  evaporated  to  dryness 
on  the  water  bath.  The  residue  is  heated  to  drive 
off  all  salts  of  ammonium,  cooled,  and  an  excess  of 
strong  sulphuric -acid  added.  The  basin  should  be 
carefully  heated  until  acid  fumes  cease  to  come  off 


Analysis  of  Sized  Grey  Cloth. 


and  afterwards  strongly  ignited.  A  piece  of  car- 
bonate of  ammonium  should  then  be  placed  in  the 
basin,  which  is  re-heated.  The  residue  is  sulphate 
of  sodium,  Na2S04.  This  should  be  cooled  and 
weighed,  and  the  weight  of  the  basin  be  deducted. 
The  amount  of  sulphate  of  sodium  found  should  be 
multiplied  by  2,  and  calculated  to  oxide  of  sodium, 
Na20. 

Na2S04    =  Na.O 
142  62 

This  is  further  calculated  to  a  percentage  of 
the  cloth  taken. 

Estimation  of  Sulphuric  Acid  and  Chlorine. — 
The  proportion  of  sodium  existing  as  chloride 
and  as  sulphate  is  determined  after  ascertaining  the 
amount  of  combined  chlorine  and  sulphuric  acid. 
For  this  purpose  another  portion  of  the  cloth  should 
be  steeped  for  several  hours  in  dilute  alcohol,  specific 
gravity  0*92,  under  the  same  conditions  as  given 
on  page  497. 

Ten  to  fifteen  grammes  of  cloth  should  be  care- 
fully weighed  and  steeped  in  exactly  250  c.c.  of  the 
dilute  alcohol  for  five  or  six  hours.  It  is  afterwards 
filtered  and  treated  as  follows: — 

(1)  Sulphuric  Acid. — 100  c.c.  of  the  filtered 
solution  should  be  placed  in  a  suitable  beaker,  the 
alcohol  boiled  off,  and  a  few  drops  of  hydrochloric 
acid  and  an  excess  of  solution  of  chloride  of  barium 


504      The  Chemistry  and  Practice  of  Sizing. 


added  in  order  to  precipitate  sulphuric  acid,  if 
present,  as  sulphate  of  barium. 

The  precipitate  should  be  collected  on  a  filter 
paper.  It  is  then  well  washed,  dried,  and  finally 
transferred  to  a  tared  porcelain  crucible.  The  filter 
paper  should  be  burnt  in  the  Bunsen's  flame  as 
follows: — It  is  first  rolled  up  into  as  small  a  compass 
as  possible,  and  then  wrapped  round  with  a  platinum 
wire  so  as  to  form  a  ca^e.  This  ash  is  added  to 
the  contents  of  the  crucible,  and  the  whole  ignited 
for  some  time.  The  crucible  is  then  allowed  to  cool, 
and  afterwards  a  drop  of  sulphuric  acid  (to  convert 
any  sulphide  of  barium,  formed  by  reduction,  into 
sulphate)  is  added.  The  crucible  is  again  carefully 
ignited,  cooled,  and  weighed. 

The  sulphate  of  barium  BaS04,  is  calculated  to 
S03,  each  232*8  parts  by  weight  of  BaS04  =  80 
parts  by  weight  of  S03. 

BaS04  SO:i 
2328  80 

As  100  c.c.  of  the  250  c.c.  of  original  solution 
have  been  used,  the  weight  found  will  be  two-fifths 
of  the  weight  of  S03  on  the  cloth.  The  amount 
actually  in  the  cloth  should  be  calculated,  and  then 
further  calculated  to  a  percentage. 

The  S03  found  by  this  treatment  may  have 
existed  as  magnesium  or  sodium  sulphate,  or  both, 
Calcium  sulphate  is  not  soluble  in  dilute  alcohol,  so 
that  this  salt  cannot  be  present. 


Analysis  of  Sized  Grey  Cloth.  505 


(2)  Chlorine.  — 100  c.c.  of  the  solution  in  dilute 
alcohol  should  be  placed  in  a  suitable  beaker,  the 
alcohol  boiled  off,  and  a  few  drops  of  nitric  acid  and 
an  excess  of  nitrate  of  silver  added.  The  chlorine 
is  precipitated  as  chloride  of  silver.  The  super- 
natant liquid  is  poured  off  through  a  filter  paper. 
The  chloride  of  silver  is  washed  once  or  twice  with 
hot  water,  and  the  washings  poured  over  the  filter 
paper.  The  precipitate  is  then  transferred  to  the 
filter  paper  and  the  washing  continued.  The  pre- 
cipitate is  afterwards  dried.  After  drying,  as  much 
of  the  precipitate  as  possible  is  removed  from  the 
paper  to  the  crucible.  The  filter  paper  is  then 
burnt  on  the  inverted  lid  of  the  crucible.  It  is 
afterwards  moistened  with  a  drop  of  nitric  acid, 
warmed,  and  a  drop  of  hydrochloric  acid  added. 
It  is  then  evaporated  to  dryness,  after  which  the 
lid  is  replaced  on  the  crucible,  and  the  whole  ignited 
until  the  edges  of  the  mass  of  chloride  of  silver 
begin  to  fuse.  The  crucible  and  contents  are 
allowed  to  cool  and  then  weighed.  Every  143*5 
parts  of  chloride  of  silver  contain  35*5  parts  of 
chlorine. 

AgCl  CI 
!435  35*5 

The  amount  of  chlorine  found  is  two-fifths  of  the 
actual  chlorine  present  as  chlorides  in  the  weight  of 
cloth  taken.  The  actual  weight  is  calculated,  and 
then  further  calculated  to  a  percentage, 


506       The  Chemistry  and  Practice  of  Sizing. 


In  the  absence  of  sulphate  of  magnesium, 
sulphate  of  sodium,  sulphate  of  calcium,  chloride  of 
sodium,  and  chloride  of  calcium,  the  problem  of 
uniting  the  bases  found  with  the  respective  acid 
radicals  is  an  easy  one.  Thus  the  whole  of  the  zinc 
will  exist  as  chloride  of  zinc,  and  the  whole  of  the 
magnesium  will  exist  as  chloride  of  magnesium. 
From  the  percentage  of  oxide  of  zinc  found  by 
analysis  the  weight  of  chloride  of  zinc  may  be 
readily  calculated,  and  from  the  percentage  of  oxide 
of  magnesium  found  by  calculation,  the  chloride 
of  magnesium  may  be  calculated. 

The  presence  of  other  chlorides  and  sulphates 
increase  the  difficulty  of  the  problem.  Consider- 
able experience  is  then  required  in  order  to 
rationally  combine  the  different  bases  with  their 
acid  radicals. 

The  following  may  be  taken  as  a  general  method 
of  procedure: — Where  zinc,  magnesium,  chlorine, 
and  sulphuric  acid  are  found,  with  only  a  trace  of 
sodium  and  calcium — 

(a)  The  whole  of  the  zinc  should  be  combined 
with  sufficient  chlorine  to  saturate  it,  forming  chloride 
of  zinc. 

(b)  The  sulphuric  acid  radical,  S03,  will  combine 
with  sufficient  oxide  of  magnesium  to  form  sulphate 
of  magnesium. 

MgO    +    S03    =^  MgS04 
40  80  120 


Analysis  of  Sized  Grey  Cloth. 


507 


(c)  The  balance  of  oxide  of  magnesium  will 
combine  with  sufficient  chlorine  to  saturate  the 
whole  of  it,  forming  chloride  of  magnesium. 

If  calcium  has  been  found,  and  there  is  more 
chlorine  than  can  be  taken  up  by  the  zinc  and  mag- 
nesium, after  the  S03  has  been  saturated,  the  calcium 
will  exist  as  chloride  of  calcium. 

To  determine  whether  the  whole  of  the  calcium 
in  the  cloth  exists  as  chloride,  the  following  method 
is  useful: — A  measured  portion  of  the  solution, 
obtained  by  digesting  a  weighed  portion  of  the 
cloth  in  dilute  alcohol,  is  operated  upon.  This  is 
tested  for  calcium  in  the  usual  way.  If  calcium  be 
found  it  will  have  existed  as  chloride  of  calcium, 
CaCl2,  and  the  operation  must  be  conducted  so  as 
to  allow  a  quantitative  estimation  to  be  made.  The 
amount  of  chloride  of  calcium  present  should  be 
calculated  to  a  percentage  of  the  cloth  originally 
taken.  From  this  percentage  of  chloride  should  be 
calculated  its  equivalent  of  CaO,  and  this  must  be 
deducted  from  the  total  amount  of  oxide  of  calcium 
found  previously.  The  balance  of  oxide  of  calcium 
will  exist  as  sulphate,  and  will  of  course  saturate  its 
equivalent  of  S03 


CaO 
56 


+ 


SO, 

80 


CaS04 
136 


If  sodium  has  been  found  it  may  exist  either  as 
sulphate  or  chloride,  or  both. 


508      The  Chemistry  and  Practice  of  Sizing. 

If,  after  combining  the  zinc,  magnesium,  and 
calcium  with  the  chlorine  and  sulphuric  acid,  there 
still  remains  an  excess  of  uncombined  chlorine  and 
sulphuric  acid,  then  both  chloride  and  sulphate  of 
sodium  are  present,  but  if  only  chlorine  be  left 
uncombined,  then  the  salt  is  chloride  of  sodium;  or 
if  only  sulphuric  acid  be  left  uncombined,  then  the 
salt  is  sulphate  of  sodium.  Every  62  parts  of  oxide 
of  sodium  by  weight  will  require  71  of  chlorine, 
producing  117  parts  of  chloride  of  sodium. 

Na20    +     Cl2    =    2NaCl    +  O 
62  71  117  16 

Every  62  parts  of  oxide  of  sodium  will  require 
80  parts  of  S03  producing  142  parts  of  Na2S04 

Na20    +    SO.  Na2S04 
62  80  142 

The  following  are  the  deductions  which  should 
be  made  from  the  total  percentage  of  ash  found  in 
the  cloth : — 

1.  — The  percentage  of  ash  natural  to  cotton  fibre 

=  1  per  cent,  of  cotton  found, 

2.  — The  percentage  of  oxide  of  magnesium  which 

exists  as  chloride. 

3.  — The  percentage  of  sulphate  of  magnesium. 

4.  — The  percentage  of  chloride  of  calcium. 

5.  — The  percentage  of  sulphate  of  calcium. 

6.  — The  percentage  of  chloride  and  sulphate  of 

sodium. 


Analysts  of  Sized  Grey  Cloth. 


509 


After  these  deductions  have  been  made  10  per 
cent,  should  be  added  to  the  balance  of  ash  remain- 
ing for  the  moisture  natural  to  China  clay. 

Whenever  sulphate  of  sodium  or  sulphate  of 
magnesium  is  found  allowance  must  be  made  for 
the  water  of  crystallization  contained  in  them.  If  the 
analysis  has  been  made  with  the  view  of  matching 
the  cloth  at  least  twice  the  quantity  of  each  of 
these  substances  must  be  used  to  allow  for  the  water 
of  crystallization,  viz. : — 

Na2S04,  lOHoO 

142  180 
MgS04,  7ELO 

120  126 

The  amount  of  zinc  left  in  the  ash  after  ignition 
may  be  neglected  in  the  above  deductions. 

The  authors  have  known  of  cases  where  the 
chloride  of  zinc  has  been  determined  from  the  ash 
instead  of  directly  from  the  cloth.  Such  methods  are 
not  accurate  as  a  certain  amount  of  the  chloride  of 
zinc  exists  on  the  cloth  as  oxychloride  of  zinc. 
When  the  cloth  is  ignited,  a  portion  of  this  is  con- 
verted into  metallic  zinc,  which  is  volatilised  at  a 
bright  red  heat,  and  is  thus  lost.  Chloride  of  zinc 
also  volatilises  at  a  bright  red  heat,  so  that  any 
analysis  of  the  ash  for  this  substance  must  be 
inaccurate. 

As  the  responsibility  for  mildewed  cloth  fre- 
quently turns  upon  the  amount  of  chloride  of  zinc 


5 1  o      The  Chemistry  and  Practice  of  Sizing. 


present  in  the  cloth  too  much  care  cannot  be 
exercised  in  ascertaining  the  exact  quantity  of  this 
substance. 

There    now    remains    to    be    calculated  the 

amount    of   starchy    matter,    dextrin,    etc.  This 

is   obtained    by    difference.      The    whole   of  the 

ingredients  having  been  calculated  to  percentages, 

we  have  : — 

Cotton —  per  cent. 

Fibre  

Natural  Moisture  

Natural  Ash  

Size — 

Moisture   

Fatty  Matter  

China  Clay  with  natural  moisture  ... 

Chloride  of  Zinc   

Chloride  of  Magnesium   

Sulphate  of  Magnesium   

Chloride  of  Calcium   

Sulphate  of  Calcium   

Sulphate  and  Chloride  of  Sodium  ... 

Starchy  Matter  by  difference  ... 

ioo"oo 


The  starchy  matter  in  the  analysis  includes  all 
organic  matter  present  in  flour,  such  as  gluten, 
dextrin,  albumen,  etc.  It  is  seldom  necessary  to 
isolate  the  starch  and  determine  its  exact  percentage, 
as  a  cloth  analysis,  such  as  described  here,  is  gener- 
ally made  for  the  purpose  of  fixing  liability  where 
something  has  gone  wrong  with  the  cloth,  such  as 
the  development  of  mildew,  and  for  this  purpose 


Analysts  of  Sized  Grey  Cloth.  51 1 

the  organic  matter  in  flour  may  be  estimated  by 
difference. 

The  following  analyses  show  the  composition 
of  various  kinds  of  cloth  submitted  to  the  writer: — 

Analyses  of  Various  Samples  of 
Sized  Grey  Cloth. 


Percentages. 


Cloth  :— 

1 

2 

3 

4 

5 

6 

Dry  Cotton  Fibre  and  Ash 

55-8o 

62*92 

62*95 

74-89 

79-07 

83*96 

4'8o 

547 

5*47 

6-51 

6*32 

7*3° 

Size: — 

3*96 

4*02 

5*28 

2*69 

2-49 

0*71 

15*42 

8*12 

9*09 

3-88 

9'6o 

7*52 

Fatty  Matter  

4-90 

2*IO 

3*12 

2*14 

i*94 

°*43 

China  Clay,  natural   

12-54 

I5'63 

10-93 

8*63 

o*  2 1 

Chloride  of  Zinc   

0-94 

0*48 

0*46 

0*13 

0*03 

Chloride  of  Magnesium 

1*64 

1*26 

2*70 

I*!3 

o"34 

0*08 

TOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

Total  Cloth  

6o*6o 

68*39 

68-42 

81*40 

85-39 

91  "26 

Total  Size  

39'4o 

31*61 

31*58 

18*60 

14*61 

874 

IOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

IOO'OO 

Percentage  of  Zinc  to 

^Starchy  Matter... 

07*6 

i*i6 

275 

1*20 

o'8i 

O'OI 

6*09 

5*9i 

5-06 

3*3° 

0*31 

The  above  samples,  except  No.  1,  were 
mildewed,  and  they  will  be  referred  to  again  in 
the  next  chapter.  No.  1  sample  does  not  contain 
the  amount  of  zinc  it  should  contain,  although  it  was 
free  from  mildew  when  submitted  to  the  writer. 


5 1 2      The  Chemistry  and  Practice  of  Sizing. 
Chapter  XIV. 


Damage  to  which  Sized  Cloth  is  liable. 
Mildew  and  Iron-stains. 


MANUFACTURERS  in  Lancashire  have 
sustained  enormous  losses  from  time  to  time 
through  the  development  of  mildew  and  iron-stains 
in  sized  grey  cloth.  The  origin  of  these  forms  of 
damage  have  been  carefully  investigated,  and  the 
information  at  the  disposal  of  the  manufacturer  to- 
day is  sufficient  to  prevent  anything  like  the  serious 
losses  of  thirty  or  forty  years  ago.  Still  mildew  and 
iron-stains  are  yet  great  sources  of  trouble  and 
annoyance. 

MILDEW. 

Mildew  is  the  name  given  to  the  growth  of  a 
class  of  low  vegetable  life  known  as  fungi,  of  which 
there  are  about  two  thousand  varieties  known  to  the 
botanist,  and  these  vary  in  size  and  colour  very 
considerably. 


Mildew. 


513 


The  manufacturer  is  more  particularly  interested 
in  the  crrowths  of  funori  which  attack  "sized"  cotton 
cloth,  They  are  large  in  number,  and  characterised 
by  different  colours.  Their  origin  and  distribution 
in  a  bale  of  cotton  cloth  is  dependent  upon  the 
cause  of  their  development. 

Black  Mildew. — This  fungus  is  generally  the 
one  known  botanically  as  Tilletia,  and  is  more  often 
found  on  the  twist  and  cloth,  either  in  the  weaving 
shed  or  warehouse,  than  on  cloth  returned  from 
abroad.  Its  presence  is  generally  due  to  the  absence 
of  the  proper  proportion  of  chloride  of  zinc  in  the  size, 
or  through  the  ' 'taper"  having  run  his  yarns  too  damp. 
This  form  of  mildew  will  make  its  appearance  under 
the  latter  conditions,  even  where  there  is  sufficient 
chloride  of  zinc  to  protect  the  cloth  under  ordinary 
circumstances. 

Green  Mildew. — This  form  of  mildew  is  either 
produced  by  the  development  of  Aspergillus  glaucus 
or  Penicillium  glauctim.  Like  black  mildew  it  is 
often  found  in  a  weaving  shed,  due  to  the  causes 
mentioned  under  black  mildew. 

Yellow  Mildew. — Mildew  of  this  colour  is  very 
often  found  upon  the  cloth,  usually  spotted  over  the 
piece  in  patches  varying  in  size  from  that  of  a  pin- 
head  to  a  three-penny  piece.  It  is  generally  produced 
from  the  yellow  conceptacle  of  Aspergillus  glaucus, 
and  will  develop  with  less  air  than  the  green  conidia 
of  the  same  species. 

G2 


514      The  Chemistry  and  Practice  of  Sizing, 


Purple  Mildew. — This  form  of  mildew  is 
frequently  found  by  the  writer  in  samples  of  flour 
paste  which  have  been  left  exposed  in  the  labora- 
tory. It  has  the  appearance  as  though  the  wet  flour 
paste  had  been  marked  with  a  purple  copying-ink 
pencil.  Purple  mildew  does  not  penetrate  below 
the  surface  of  the  paste.  It  is  usual  to  find  a 
development  of  red,  green,  or  yellow  mildew  beneath 
the  purple.  W.  Thompson,  in  his  book  on  Sizing 
(1879),  calls  particular  attention  to  this  form  of 
mildew.  It  is  curious  that  in  Manchester  purple 
mildew  almost  invariably  makes  its  appearance 
on  samples  of  flour  paste  left  about  in  the 
laboratory. 

Pink  Mildew. — This  form  of  mildew  is  not 
often  found  on  "sized"  cloth,  as  it  does  not  develop 
so  quickly  as  some  other  varieties.  The  finest  crop 
ever  seen  by  the  writer  was  on  the  inside  of  half  a 
cocoa-nut  which  had  been  left  in  a  damp  cupboard. 
The  growth  on  the  cocoa-nut  was  most  luxuriant, 
and  for  months  after  it  had  been  removed  sub- 
stances liable  to  mildew,  such  as  bread,  etc., 
developed  pink  mildew  when  placed  in  the  cup- 
board. Bread  had  been  stored  previously  in  the 
cupboard  but  pink  mildew  had  never  developed 
upon  it  until  after  the  cocoa-nut  had  been  placed 
there.  Like  the  purple  form  of  mildew  pink  mildew 
is  generally  found  on  the  surface  only  of  flour  or 
starch  paste. 


Mildew. 


5*5 


Brick-Red  Mildew, — This  form  of  mildew  is 
fairly  common  in  "sized"  cloth.  It  is  very  often 
mistaken  for  iron-stains.  This  is  due  to  placing  too 
much  reliance  upon  the  usual  test  for  iron,  viz. : — The 
action  of  dilute  hydrochloric  acid  and  ferrocyanide 
of  potassium.  This  test  is  fully  described  in  the 
section  on  iron-stains.  There  is  always  sufficient 
iron  in  any  piece  of  "sized"  grey  cloth,  iron  stained 
or  not,  to  produce  the  blue  colour  unless  the  test  is 
made  very  carefully.  The  hydrochloric  acid  must 
be  used  very  dilute,  otherwise  it  will  decompose  a 
portion  of  the  ferrocyanide  of  potassium  and  produce 
the  blue  colouration. 

Brown  Mildew. — This  form  of  mildew  is  very 
often  found  on  mildewed  cloth.  It  belongs  to  the 
species  Puccinia. 

Tests  for  Mildew. — As  a  rule  the  appearance 
and  smell  of  a  sample  of  damaged  cloth  is  sufficient 
to  determine  whether  the  stain  is  due  to  mildew. 
Sometimes,  however,  the  characteristic  smell  of 
mildew  is  absent  entirely.  This  is  probably  due  to 
the  cloth  having  been  exposed  before  it  has  reached 
the  analyst. 

It  is  too  often  decided  that  a  stain  is  not 
mildew  because  the  spores  and  filaments  of 
the  fungus  cannot  be  seen  when  the  fibres  are 
examined  under  the  microscope,  As  a  matter  of 
fact  it  rarely  happens  that  any  spores  or  filaments 
can  be  recognised  on  the  yarns;  the  filaments  of 


5 1 6       The  Chemistry  and  Practice  of  Sizing. 

cotton  preventing  their  appearance  being  readily 
perceived.  Too  much  reliance  must  not  be  placed, 
therefore,  if  positive  proofs  are  not  obtained  when 
the  stain  is  examined  under  the  microscope.  Very 
often  in  such  a  case  the  stain,  if  it  be  red  or  reddish 
brown,  is  wrongly  put  down  to  iron-stain. 

In  most  cases  where  mildew  is  present  the 
particular  form  may  be  cultivated.  Care  must 
be  exercised  to  keep  out  the  spores  of  other 
species. 

The  following  tests  are  useful  where  there  is 
any  doubt  in  regard  to  a  particular  stain: — 

(1)  Treat  the  stained  cloth  with  peroxide  of 
hydrogen.  Mildew  will  often  bleach  out;  iron-stains 
are  not  affected. 

(2)  Treat  the  cloth  with  a  filtered  solution  of 
chlorinated  lime.  Mildew  will  bleach  out ;  iron-stains 
are  not  affected. 

(3)  Boil  a  portion  of  the  cloth  in  a  solution  of 
caustic  soda.  The  stains  almost  invariably  become 
tinted  purple  or  reddish  purple  by  this  treatment, 
whatever  may  have  been  the  original  colour. 

(4)  Compare  the  ash  formed  by  burning  a  piece 
of  cloth  containing  the  stain  with  the  ash  obtained 
from  a  piece  of  the  same  cloth  cut  from  an  un- 
stained portion.  If  the  stain  be  due  to  iron  there 
will  be  a  marked  difference  in  the  colour  of  the  two 
samples  of  ash.  The  portion  containing  the  stain 
will  be  of  a  reddish  yellow  whilst  the  other  ash  will 


Mildew.  5 1 7 

be  white  or  greyish  white.  This  matter  is  further 
dealt  with  under  iron-stains. 

If  the  above  test  is  made  with  cloth  which  is 
very  ''heavily "  sized,  it  will  be  necessary  to  remove 
as  much  of  the  size  as  possible  by  washing  the  cloth 
in  water,  or  treating  with  a  solution  of  malt,  as 
described  on  page  47,  and  drying  previous  to 
igniting  it  in  the  crucible.  Iron-stains  cannot  be 
removed  by  such  treatment,  but  mildew,  especially 
if  the  fungus  has  attacked  the  starch  only,  may 
be  almost  entirely  removed  along  with  the  starch. 
If  the  cotton  itself  has  been  attacked  washing  will 
not  remove  the  stain. 


LIABILITY  FOR  MILDEW. 

The  question  of  liability  where  cloth  has 
mildewed  has  frequently  to  be  determined.  There 
can  be  no  question  that  the  manufacturer  is 
responsible  if  the  cloth  does  not  contain  sufficient 
chloride  of  zinc,  or  if  the  yarns  have  been  "taped" 
too  damp.  At  the  same  time  there  are  many  cases 
where  the  manufacturer  is  held  responsible  and  yet 
he  has  taken  every  reasonable  precaution  to  prevent 
damage: — For  instance  he  is  liable  if  he  has  used 
weft  which  has  become  slightly  mildewed  through 
the  spinner  "over-damping"  the  yarn,  and  which 
may  not  show  signs  of  mildew  at  the  time.  It  is 
almost  impossible  for  him  to  place  the  blame  on  the 


5 1 8       The  Chemistry  and  Practice  of  Sizing. 


right  shoulders  after  the  damage  has  been  done. 
This  matter  was  fully  discussed  on  page  471. 

Then  again  there  seems  to  be  an  unreasonable 
responsibility  placed  upon  the  manufacturer  by  the 
merchant  who  may  make  a  claim  for  damage  for 
mildew  on  cloth  which  has  been  stored  for  longperiods. 
During  times  of  bad  trade  it  is  no  uncommon  thing 
for  claims  to  be  made  on  cloth  wrhich  has  been  stored 
from  12  month's  to  2  years.  The  manufacturer  has 
no  control  over  the  storage  nor  even  over  the  packing 
of  the  cloth.  The  goods  remain  in  the  original  bales 
until  sold  and  if  they  are  found  to  be  damaged  by 
mildew  when  opened  a  claim  is  put  in.  This  is 
not  fair  to  the  manufacturer  when  cloth  is  shipped 
to  hot  countries  like  India  and  China.  There 
should  be  a  reasonable  time-limit  placed  upon  the 
merchant's  right  of  claim. 

The  responsibility  for  damage  from  mildew  may 
very  often  be  settled  by  making  an  analysis  of  the 
cloth  in  order  to  determine  the  proportions  of  actual 
chloride  of  zinc  to  the  starchy  matter  present  in  the 
"size."  Experience  has  shown  that  8  parts  of  chloride 
of  zinc  to  100  of  starchy  substances  are  sufficient  to 
preserve  cloth  from  mildew,  providing  it  is  not 
subjected  to  unreasonable  treatment,  either  by  the 
manufacturer,  or  by  those  people  who  handle  it.  after 
it  has  left  the  manufacturer. 

Unfortunately  for  manufacturers  it  is  customary 
for  most  analysts  who  have  no  practical  experience  of 


Mildew. 


519 


" sizing"  and  weaving  to  invariably  place  the  blame 
for  the  development  of  mildew  on  cloth  to  the  use 
of  an  excessive  quantity  of  chloride  of  magnesium 
in  the  "size."  As  a  matter  of  fact  manufacturers  who 
are  accustomed  to  make  "heavy"  sized  goods  rarely 
use  excessive  quantities  of  chloride  of  magnesium. 
There  are  many  reasons  for  this.  In  the  first  place 
a  well  balanced  "mixing"  for  "heavy"  sizing  does 
not  require  an  excessive  amount  of  chloride  of  mag- 
nesium, because  the  object  of  every  manufacturer, 
who  knows  his  business  in  "heavy"  sizing,  is 
to  get  the  desired  weight  with  the  cheapest  in- 
gredient, viz: — China  clay.  On  this  account  the 
smallest  proportion  of  flour,  and  the  largest  pro- 
portion of  China  clay  that  can  be  got  to  adhere  to 
the  twist,  is  used.  Flour  or  starch  produces  a 
harsh  yarn  whilst  China  clay  has  a  tendency  to 
soften  it.  Therefore,  if  a  small  proportion  of  flour 
be  used  much  smaller  proportions  of  the  softening 
ingredients,  such  as  tallow  and  chloride  of  mag- 
nesium, may  also  be  used.  On  the  other  hand,  if  a 
large  proportion  of  flour  be  used  the  yarns  would  be 
harsh,  and  it  would  be  necessary  to  use  a  very  much 
larger  proportion  of  chloride  of  magnesium  and 
tallow  to  soften  them.  As  tallow  is  the  most 
expensive  ingredient  employed  in  sizing  the 
"mixing"  would  be  a  costly  one. 

It  must  be  remembered  that  there  is  a  limit  to 
the  use  of  chloride  of  magnesium  as  a  "softener" 


520      The  Chemistry  and  Practice  of  Sizing. 

beyond  which  the  manufacturer  may  not  go  without 
suffering  damage.  It  has  been  tried  over  and  over 
again  to  substitute  chloride  of  magnesium  for  tallow, 
but  there  has  always  been  one  result  when  the 
limit  has  been  passed,  viz. : — iron-stains  have 
developed  in  the  weaving  shed.  This  matter  is 
more  fully  described  under  iron-stains. 

The  authors  are  strongly  of  opinion  that  very 
few  cases  of  mildew  are  really  traceable  to  the  use 
of  chloride  of  magnesium  where  chloride  of  zinc  has 
been  used  in  proper  proportions. 

Practical  experience  has  shown  that  where  an 
attempt  has  been  made  to  use  an  excessive  amount 
of  this  substance,  at  the  expense  of  the  tallow,  it  has 
soon  been  given  up.  This  is  accounted  for  in  several 
ways.  In  the  first  place,  because  of  the  trouble  and 
loss  sustained  through  iron-stains  developing  in  the 
weaving  shed,  and  secondly,  because  an  excessive 
quantity  of  chloride  of  magnesium  would  make  the 
size  and  the  yarns  so  damp  that  it  would  give  rise 
to  the  condition  known  as  "choving."  That  is,  the 
damp  size  would  rub  off  as  it  passed  through  the 
healds,  thus  causing  the  eyes  of  the  healds  to  become 
made  up. 

In  spite  of  the  fact  that  chloride  of  magnesium 
is  rarely  used  in  excessive  quantities,  it  is  painful  to 
see  experts  commonly  reporting  that  this  ingredient 
is  the  cause  of  mildew  in  cloth  which  has  been  sent 
to  them  for  analysis.    The  authors  have  come  across 


Mildew. 


521 


several  cases  recently  which  have  been  submitted  to 
analysts  who  have  reported  that,  44  whilst  finding  the 
proportion  of  chloride  of  zinc  to  be  sufficient  to 
preserve  the  cloth  from  mildew,  the  proportion  of 
chloride  of  magnesium  has  caused  the  cloth  to  absorb 
moisture  to  such  an  extent  as  to  cause  mildew."  In 
several  cases  the  cloth  has  been  submitted  to  the 
writer,  who  has  found  practically  the  same  proportions 
of  the  chlorides  of  zinc  and  magnesium  as  found 
by  the  other  analysts.  But,  instead  of  the  pro- 
portion of  chloride  of  magnesium  being  excessive, 
it  was  present  in  the  minimum  amount  which 
could  be  used  for  the  class  of  sizing.  In  each  case 
the  analyst  was  bold  enough,  in  his  innocence,  to 
tell  the  manufacturer  to  reduce  the  amount  of 
chloride  of  magnesium  in  his  44 mixing"  by  one  half. 
The  manufacturer  knew  perfectly  well  that  such 
a  reduction  was  not  possible  in  practice,  and  he 
has  laughed  at  the  folly  of  44 expert  advice."  Two 
cases  which  have  occurred  recently  where  this  advice 
was  given  will  be  described  in  detail. 

In  the  first  case  the  manufacturer  knew  that 
the  damage  had  been  caused  at  his  own  mill 
through  storing  the  cloth  against  a  very  damp  wall 
before  it  was  sent  to  Manchester.  He  thought  that 
conflicting  44 expert"  evidence  might  help  him  to 
avoid  any  claim  for  the  damage  altogether,  or 
induce  the  shipper  to  meet  him  in  the  claim 
for  damages. 


522       The  Chemistry  and  Practice  of  Sizing, 

In  the  second  case  the  manufacturer  had  sold 
" heavy"  sized  shirtings  to  a  Manchester  merchant, 
and  after  the  goods  had  been  in  India  about  18 
months  some  of  the  pieces  were  found  to  be  covered 
with  mildew.  One  portion  of  the  damaged  cloth 
was  sent  to  a  firm  of  analysts  by  the  merchants, 
whilst  another  portion  was  sent  by  the  manufacturer 
to  the  writer. 

The  writer  reported  that  the  mildew  was  due  to 
moisture,  and  that  the  moisture  must  have  come  in 
contact  with  the  goods  after  they  had  left  the 
manufacturer.  He  based  his  report,  in  the  first 
place,  upon  the  fact  that  the  cloth  contained 
sufficient  chloride  of  zinc  to  prevent  the  develop- 
ment of  mildew  unless  it  had  been  unfairly  treated. 
In  the  second  place  because  the  cloth  contained  a 
very  small  proportion  of  chloride  of  magnesium  and 
flour,  with  a  very  large  proportion  of  China  clay. 
If  the  moisture  had  come  in  contact  with  the  cloth 
before  it  left  the  manufacturers  hands  mildew  would 
have  shown  before  the  cloth  had  been  shipped,  or,  if 
it  had  been  caused,  as  is  very  often  the  case, 
through  the  taper  running  the  yarns  damp,  it  would 
have  shown  on  the  weavers  beam  in  the  weaving 
shed.  As  a  matter  of  fact  it  was  not  found  until  the 
cloth  had  been  in  India  for  the  time  stated,  and  then 
on  a  few  pieces  only.  The  manufacturer  was  in  the 
habit  of  steeping  large  quantities  of  flour  with 
chloride  of  zinc  in  the  proportion  of  four  gallons  of 


M ildew. 


523 


zinc  to  each  sack  of  flour.  If  he  had  omitted  to  put 
in  the  right  quantity  of  zinc,  or  if  the  damage  had 
been  due  to  an  excessive  quantity  of  chloride  of 
magnesium,  many  thousands  of  pieces  would  have 
been  damaged,  instead  of  a  few  dozen  pieces  only. 
In  this  case  the  manufacturer  was  also  informed 
that  he  would  have  to  reduce  the  chloride  of 
magnesium  by  one  half  if  he  was  desirous  of 
preventing  a  re-occurrence  of  the  damage.  Had 
this  advice  been  followed  it  would  have  been 
impossible  to  successfully  weave  the  yarn. 

The  most  curious  part  about  the  report  was  that 
the  analysis  coincided  with  the  writer's  analysis  so 
far  as  the  proportions  of  chloride  of  zinc  and  of 
chloride  of  magnesium  were  concerned,  but  a  con- 
siderable difference  was  shown  in  the  proportion  of 
total  cotton  fibre  and  size.  This  difference  was  still 
more  marked  when  the  size  came  to  be  calculated 
to  a  percentage  on  the  twist,  instead  of  upon  the 
total  cloth.  In  the  writer's  report  it  was  shown  that 
there  was  125  per  cent,  of  size  on  the  twist,  whereas 
in  the  report  submitted  by  the  other  analyst  the 
amount  of  size  on  the  twist,  on  calculation,  was  190 
per  cent.  As  a  matter  of  fact  the  twist  had  been 
sized  140  per  cent,  only,  and  there  had  been  the 
usual  loss  between  tapeing  and  weaving.  It  is  a 
well-known  fact  amongst  all  sizers  that  it  is  easier  to 
produce  "light"  beams  in  "heavy"  sizing,  than  to 
produce  beams  heavier  than  that  for  which  the 


524       The  Chemistry  and  Practice  of  Sizing. 

" mixing"  is  intended.  It  was  quite  impossible 
for  the  twist  to  be  sized  to  the  extent  of  190 
per  cent,  with  a  140  per  cent,  "mixing."  The 
manufacturer's  books  proved  that  140  per  cent, 
was  the  amount  of  size  actually  put  on  the 
twist. 

It  was  many  months  after  the  analysis  had 
been  made  that  the  writer  learnt  the  true  cause  of 
the  mildew.  One  day  his  client  admitted  that  he 
had  always  known  its  origin.  He  had  been 
experimenting  by  sending  his  cloth  to  Manchester 
by  read  instead  of  by  rail,  and  on  one  occasion  the 
cloth  had  been  caught  in  an  unexpected  shower  of 
rain.  The  carter  had  not  sufficient  covering  to 
protect  the  cloth,  and  this  accounted  for  it  receiving 
moisture  after  it  had  left  the  hands  of  the  manu- 
facturer. A  great  many  cases  of  mildew  owe  their 
origin  to  cloth  coming  in  contact  with  rain.  The 
authors  have  often  noticed  how  carelessly  grey  cloth 
is  handled  in  Manchester.  It  is  a  common  sight  to 
see  cloth  being  carried  from  lurries  into  the  ware- 
houses on  wet  days  without  any  protective  covering. 
The  rain  falls  upon  the  cloth,  which  is  afterwards 
packed  in  a  damp  state  into  bales,  and  then  shipped 
to  India  or  China.  There  need  be  little  cause  for 
surprise  that  when  the  bales  are  opened  the  goods 
are  found  to  be  mildewed.  Until  cloth  receives 
more  reasonable  treatment  at  the  hands  of  shippers 
mildew  will  always  be  a  source  of  loss  and  dispute, 


Mildew. 


525 


especially  in  cases  where  the  manufacturer  has 
been  using*  the  minimum  safe  quantity  of  chloride 
of  zinc. 

Cases  are  not  unknown  where  mildew  has 
formed  on  "pure'  sized  grey  cloth  through  being 
packed  in  damp  card-board  boxes.  The  flour 
paste  used  in  making  the  boxes  had  not  been 
thoroughly  dry  before  the  cloth  had  been  put 
into  them.  The  result  was  that  the  paste  first 
mildewed,  and  afterwards  the  growth  extended 
to  the  cloth. 

It  is  often  a  very  difficult  matter  to  prove  who 
is  responsible  for  the  damage  due  to  the  formation 
of  mildew  on  cloth  which  has  been  shipped  abroad. 
As  a  rule,  however,  a  careful  analysis  of  a 
sample  of  the  cloth,  and  an  examination  of  a  bale 
of  the  mildewed  goods,  together  with  a  practical 
knowledge  of  sizing,  will  give  an  expert  all  the 
information  necessary  to  locate  the  source  of  the 
damage. 

It  will  probably  be  interesting  and  instructive 
to  the  reader  to  have  a  few  instances  of  mildew, 
with  the  cause  of  the  damage,  described. 

In  one  case  a  manufacturer  sent  for  analysis 
some  fine  dhooties,  made  from  Egyptian  yarns. 
These  goods,  which  were  supposed  to  be  "pure"  sized, 
were  badly  stained  with  mildew,  but  the  fungus  had 
attacked  the  starchy  matter  of  the  size  only 
leaving  the  cotton  fibre  stained  but  undamaged. 


526      The  Chemistry  and  Practice  of  Sizing, 


An  analysis  of  the  cloth  gave  the  following  result: — 


Cloth: —  PerCent. 

Cotton  Fibre  and  Natural  Ash    79*0 7 

Natural  Moisture    6*32 

Size: — 

Moisture    2*49 

Starchy  Matter    9*607 

Fatty  Matter   I'93S 

Mineral  Matter  in  Size   '578 

IOO'OOO 

Total  Cloth   85*39 

Total  Size   14*61 


IOO'OO 

Excess  Moisture   o*8i 

Mineral  Matter:— 

China  Clay    0*20 

Chloride  of  Magnesium    °*342 

Chloride  of  Zinc    0*036 


o-578 

This  cloth  should  not  have  contained  China 
clay  or  chloride  of  magnesium,  and  the  manufacturer 
wrote  to  say  that  he  never  used  these  ingredients 
for  these  goods.  An  investigation  at  the  mill 
showed  how  they  had  got  into  the  size,  and  at  the 
same  time  explained  the  cause  of  the  damage. 

It  was  the  practice  to  make  "pure  mixings"  in 
a  beck  which  had  been  used  previously  for  "mixings" 
of  a  "heavier"  sort.  The  size  mixer  was  in  the 
habit  of  running  off  as  much  of  the  old  size  as 
possible,  but  he  rarely  took  the  trouble  to  clear  out 
the  beck  entirely.  The  result  was  that  a  fair 
quantity  of  size  from  a  "mixing"  containing  China 


Mildew. 


527 


clay  and  chloride  of  magnesium  was  occasionally 
left  in  the  beck  and  a  "pure  mixing"  made  on 
the  top  of  it. 

This  accounted  for  the  presence  of  chloride  of 
magnesium  and  China  clay  in  the  goods  which  had 
mildewed.  A  very  small  quantity  of  chloride  of 
magnesium  is  liable  to  produce  mildew  in  "pure'  sized 
cloth  on  account  of  the  moisture  it  absorbs.  It  is 
not  customary  to  use  preservatives  of  any  descrip- 
tion in  these  goods.  In  the  case  mentioned  above 
there  was  a  small  quantity  of  chloride  of  zinc  present, 
but  it  was  not  sufficient  to  preserve  the  goods  from 
mildew  in  the  presence  of  chloride  of  magnesium. 

Manufacturers  who  make  a  variety  of  "sorts" 
cannot  be  too  careful  in  insisting  that  all  "pure" 
mixings  are  made  in  clean  becks.  It  is  a  well- 
known  fact  that  "pure"  sized  goods  are  more  liable 
to  mildew  than  "heavy"  sized  goods  if  they  come 
in  contact  with  even  a  small  amount  of  moisture.  The 
reason  is,  of  course,  that  "pure"  sized  goods  rarely  con- 
tain antiseptics  of  any  description,  whereas  "heavy" 
sized  goods  usually  contain  sufficient  antiseptic  sub- 
stances to  prevent  the  formation  of  mildew. 

It  is  not  a  matter  of  much  concern  if  mildew 
forms  on  cloth  which  is  intended  to  be  bleached, 
unless  the  cotton  fibre  is  attacked,  because  the 
mildew  is  easily  washed  out  in  the  bleaching 
operations.  But  if  the  goods  have  to  be  sold  in  the 
grey  state  it  is  a  very  serious  matter. 


528      The  Chemistry  and  Practice  of  Sizing. 


Mildew  is  frequently  caused  in  "medium"  and 
"heavy "  sized  goods  on  account  of  the  size  mixer 
omitting  to  put  the  full  quantity  of  chloride  of  zinc 
into  the  mixing.  Such  an  instance  came  under  the 
writer's  notice  a  few  years  ago. 

The  manufacturers  in  this  case  sent  the  writer 
samples  of  "heavy"  sized  cloth  which  were  badly 
mildewed,  together  with  samples  of  a  similar  cloth 
which  they  were  then  making,  and  which  were 
supposed  to  be  sized  in  a  similar  manner  and  with 
a  similar  "mixing  "  to  the  goods  which  had  mildewed 
abroad.  An  analysis  of  both  samples  was  made 
with  the  following  results: — 


Cotton  and  Natural  Moisture 
Size  : — 

Moisture   

Starchy  Matter   

Fatty  Matter  

Mineral  Matter  

Excess  Moisture  

Mineral  Matter  consists  of  :— 

China  Clay  

Chloride  of  Magnesium 
Chloride  of  Zinc  

Chloride  of  Zinc  to  Starch... 


Percentages. 


Mildewed 


6839 

4'G2 
8*12 

210 

1737 


IOO'OO 


ri6 


1*26 
0-48 


Free  from 
Mildew. 


68-47 

3*4 
8  01 

2*2  1 

i7'47 


IOO'OO 


o  98 


14-96 

157 
0-94 


!7'37 


5*9i 


17*47 


11  73 


Mildew. 


529 


From  the  analysis  it  will  be  seen  that  the  cloths 
were  practically  the  same,  excepting  that  the 
mildewed  cloth  contained  only  half  the  percentage 
of  chloride  of  zinc  contained  in  that  which  was 
free  from  mildew. 

There  was  no  doubt  at  all  in  this  case.  The 
size  mixer  had  forgotten  to  put  in  a  portion  of  the 
chloride  of  zinc.  This  particular  firm  was  in  the 
habit  of  steeping  the  flour  with  a  portion  of  the 
chloride  of  zinc  only,  afterwards  adding  the  remainder 
to  each  "mixing"  as  it  was  completed.  This  is  a 
very  dangerous  practice  as  it  is  always  possible  for 
the  size  mixer  to  forget  to  add  the  second  portion. 
If  the  whole  of  the  chloride  of  zinc  had  been  mixed 
with  the  flour  as  advised  by  the  authors,  and  if  the 
quantities  were  invariably  checked  by  a  responsible 
man  at  the  time,  it  would  have  been  impossible  to 
make  a  mistake  of  this  kind. 

It  is  not  always  the  fault  of  the  size  mixer  that 
too  little  chloride  of  zinc  is  present  in  the  cloth. 
Instances  are  not  unknown  where  the  right  number 
of  gallons  have  been  used,  but  the  zinc  has  been 
adulterated  to  such  an  extent  that  mildew  has 
occurred.  It  is  always  difficult  to  place  the  respon- 
sibility for  mildew  in  such  cases,  as  manufacturers 
rarely  keep  samples  of  any  of  the  ingredients  they 
have  used.  The  only  way  to  avoid  such  risks  is  to 
have  every  cask  of  zinc  tested  before  it  is  used, 
if  only  by  means  of  the  hydrometer. 

H2 


530       The  Chemistry  and  Practice  of  Sizing. 

A  curious  case  of  mildew  came  under  the  writer's 
notice  some  few  years  ago.  A  piece  of  grey  cloth 
having  an  orange  border  on  one  selvedge  and  a  red 
border  on  the  other,  was  sent  to  his  laboratory  with 
a  note  calling  attention  to  the  orange  border, 
which  was  slightly  discoloured  in  places.  The  dis- 
colouration was  due  to  the  presence  of  little  yellow 
spots  in  the  orange  coloured  yarns.  The  orange 
dye  was  chrome  orange  (oxychromate  of  lead). 
The  first  thing  to  suggest  itself  was  that  some  kind 
of  acid  had  come  in  contact  with  the  dye,  and 
reduced  the  oxychromate  of  lead  to  the  yellow 
chromate. 

A  further  examination  of  the  body  of  the  cloth 
showed  minute  traces  of  yellow  mildew,  only  notice- 
able after  most  searching  examination,  and  which 
would  probably  never  have  been  seen  had  the 
orange  border  not  been  discoloured. 

The  yellow  stains  in  the  orange  coloured  yarns 
were  not  due  to  the  colour  of  the  yellow  mildew,  but 
to  the  reduction  of  the  orange  oxychromate  of  lead 
to  yellow  chromate  by  the  action  of  the  acids 
produced  in  the  development  of  the  mildew. 

Experiments  were  made  which  proved  that 
slightly  sour  or  mildewed  flour  would  discharge  the 
orange  dye  and  produce  a  yellow.  Orange  chrome 
dye,  either  for  cloth  sold  in  the  grey,  or  for  bleach- 
ing, has  many  objections.  This  matter  is  further 
discussed  under  bleaching. 


Mildew, 


53i 


Another  interesting  case  which  might  be 
mentioned  was  one  in  which  the  writer  was  called 
in  as  arbitrator.  The  damaged  cloth  was  a  " heavy" 
" sized"  coloured  bordered  clhootie,  the  coloured  yarns 
of  which  were  "pure"  sized  as  is  usually  the  case 
with  this  class  of  goods.  On  examination  it  was 
found  that  the  cloth  was  stained,  but  the  stain 
appeared  only  where  the  coloured  border  had  been 
folded  in  contact  with  the  grey  cloth. 

One  expert  on  behalf  of  the  manufacturer  said 
that  the  stains  were  due  to  the  dye  having  run  when 
the  goods  were  pressed  in  the  packing,  and  that  the 
fault  was  due  to  inferior  dyeing.  Another,  who  was 
acting  for  the  merchant,  reported  that  the  damage 
was  caused  through  the  use  of  bad  tallow  in  the 
"mixing."  The  analyst  for  the  dyers  of  the  yarns 
said  that  the  stains  were  due  to  mildew,  but  he  was 
unable  to  say  how  they  were  caused,  because  he 
had  found  by  an  analysis  of  the  cloth  that  it 
contained  a  very  large  proportion  of  chloride  of  zinc. 
In  fact,  so  far  as  the  body  of  the  cloth  was  concerned, 
the  conditions  were  altogether  unfavourable  to  the 
development  of  mildew. 

A  careful  examination  of  the  border  showed 
that  it  was  mildewed.  This  mildew  was  caused  by 
the  coloured  yarns  having  been  "taped"  too  damp. 
It  had  developed  whilst  the  yarn  and  cloth  were  in 
the  weaving  shed,  but  the  dark  colours  of  the  dye  had 
hidden  it.    After  the  cloth  was  packed  and  pressed 


532      The  Chemistry  and  Practice  of  Sizing, 

the  mildew  had  "  marked  off"  on  the  grey  cloth,  thus 
making  its  presence  apparent. 

It  is  a  well-known  fact  amongst  all  makers  of 
coloured  bordered  goods  containing  "heavy"  sized 
grey  yarns  and  "pure"  sized  coloured  yarns,  that 
there  is  a  great  danger  of  mildew  forming  if  the 
coloured  borders  are  not  run  very  dry.  Attention 
has  already  been  called  to  the  importance  of  running 
the  coloured  yarn  dryer  than  the  grey  yarn  on 
page  385.  In  this  particular  case  no  precautions 
had  been  taken  to  dry  the  coloured  yarn  more  than 
the  grey  yarns.  The  manufacturer  had  neither  a 
special  drying  cylinder,  nor  had  he  arranged  to 
run  the  yarn  next  to  the  face  of  the  cylinder,  as 
described  on  page  386.  This  is  a  matter  which 
should  be  more  seriously  considered  by  manu- 
facturers of  coloured  bordered  goods.  If  the 
coloured  yarns  were  run  through  a  "size"  containing 
some  form  of  preservative  a  great  deal  of  the 
danger  would  be  removed.  Chloride  of  zinc  is  not 
suitable  for  certain  coloured  yarns,  as  it  affects  the 
colours,  but  there  is  no  such  objection  to  the  use  of 
salicylic  acid  or  carbolic  acid,  and  these  substances 
are  sufficiently  powerful  to  prevent  mildew  if 
rightly  used. 

Mildew  is  very  often  formed  on  goods  which 
are  woven  with  a  number  of  thick  threads  or  cords 
in  the  selvedge.  The  reason  of  this  is  that  the 
thick  threads  can  be  dried  properly  only  with  the 


Iron-stains. 


533 


greatest  difficulty.  It  would  be  better  to  "cramp"  a 
number  of  threads  through  the  heald  instead  of 
using  one  thick  thread  where  a  cord  is  required. 
The  same  effect  would  be  produced  in  the  cloth,  and 
the  finer  threads  could  be  thoroughly  dried  when 
passing  over  the  drying  cylinders.  As  a  further 
precaution  it  would  be  advisable  to  use  salicylic  acid 
in  the  "size"  for  all  goods  which  contain  selvedges 
made  from  thicker  yarns  than  those  contained  in 
the  body  of  the  cloth. 


IRON  STAINS: 
Their  Origin,   Development,  and  Prevention. 

Iron-stains  are  a  prolific  source  of  annoyance  and 
loss  to  manufacturers  of  ''grey"  cotton  cloth.  The 
origin  of  these  stains  may  be  traced  to  many  sources. 
Very  often  they  occur  where  iron  does  not  exist  as 
an  impurity  in  the  "size"  itself.  For  convenience  of 
description  the  authors  have  divided  iron-stains  into 
three  classes,  viz. : — 

(1)  Stains  which  occur  in  the  form  of  a  broad 
band  across  the  piece  of  cloth.  These  stains 
generally  occur  in  the  spring  and  summer,  and 
disappear  after  a  time  without  any  apparent  cause. 

(2)  Stains  which  occur  in  the  form  of  spots,  and 
patches,  and  which  develop  after  the  cloth  has 
been  woven. 


534      The  Chemistry  and  Practice  of  Sizing. 

(3)  Stains  which  are  due  to  apparent  causes, 
such  as  water  dropping  on  the  cloth  in  the  loom, 
"black  oil,"  etc.,  etc. 

Cloth  Stained  with  a  Broad  Band  across 
the  Piece. — This  class  of  stains  is  caused  by  the 
yarn  and  cloth  coming  in  contact  with  iron  portions 
of  the  loom  which  have  rusted,  such  as  the  reeds, 
the  temple  roller,  and  the  front  rest.  Under 
ordinary  circumstances  the  size  should  not  exert 
any  corrosive  action  on  the  loom,  but  if  the 
conditions  are  suitable  rusting  will  take  place, 
and  the  stains  will  form  on  the  cloth  by  rubbing 
against  these  rusty  places.  This,  in  very  bad 
cases,  will  occur  in  a  single  night,  but  generally 
it  takes  place  during  the  week-end,  when  the 
looms  are  stopped  for  a  longer  period.  The  stain 
first  shows  on  the  front  rest  and  temple  roller,  and 
afterwards  on  the  warp  which  has  passed  through 
the  reeds  after  the  loom  has  been  running  a  minute 
or  two.  This  stain  continues  to  form  until  the  rust 
is  removed  by  the  friction  of  the  yarn. 

The  rusting  of  the  loom  may  be  due  to  several 
causes : — 

(1)  To  the  presence  of  acids  in  the  sizing 
ingredients. 

(2)  To  the  presence  of  acids  in  the  water 
used. 

(3)  To  the  presence  of  too  small  a  proportion 
of  tallow,  and  too  large  a  proportion  of  deliquescent 


Iron-stains. 


535 


substances,  such  as  the  chlorides  of  magnesium 
and  calcium,  in  the  size. 

(i)  The  presence  of  acid  in  the  size  may  be 
detected  by  means  of  blue  litmus  paper,  as  previously 
directed.  If  acid  be  present,  it  is  necessary  to  find 
which  ingredient  contains  it.  The  various  in- 
gredients should  be  carefully  tested  for  acid  as 
directed.  The  water  used  for  the  "mixing"  should 
be  most  carefully  tested,  as  it  is  very  often  the 
source  of  the  trouble,  especially  where  the  proportion 
of  tallow  in  the  size  is  rather  small. 

Sometimes  this  rusting  of  the  loom  occurs  inter- 
mittently. There  does  not  seem  to  be  any  apparent 
cause  why  it  develops  or  why  it  disappears,  as  no 
chancre  has  been  made  in  the  size  "mixingr."  Where 

o  o 

this  condition  exists  it  will  generally  be  found  that  the 
manufacturer  ferments  his  flour.  As  the  products  of 
fermentation  will  vary  according  to  the  class  of  flour 
being  treated,  it  is  possible  at  one  time  to  get  a 
very  acid  product,  whilst  at  another  time  there  may 
be  very  little  acid  produced.  Fermented  flour 
should  always  be  neutralised  with  alkali.  This 
wrould  prevent  iron-stains  arising  from  this  source. 

Tallow,  which  contains  acid,  may  be  the  cause  of 
the  trouble,  especially  if  it  contains  mineral  acid. 
One  consignment  may  contain  acid,  whilst  the 
next  may  be  quite  free  from  it.  This  would 
cause  the  loom  to  rust  at  one  time,  and  not  at 
another. 


536       The  Chemistry  and  Practice  of  Sizing, 

The  water  used  for  the  size  "mixings"  may  give 
rise  to  two  forms  of  iron-stains.  One  form  may  be 
produced  by  the  acids  contained  in  it  acting  on  the 
loom,  and  the  other  by  their  acting  on  the  pipes 
through  which  the  water  passes. 

Many  cases  have  occurred  where  iron-stains 
have  formed  through  the  " taper"  using  water  which 
has  stood  over-night  in  the  pipes  for  diluting  his 
size.  The  pipes  have  become  corroded  and  the 
rust  has  been  carried  down  when  the  first  water 
has  been  run  out.  The  effect  of  this  would  be  to 
form  iron-stains  which  would  probably  develop 
during  the  time  the  yarn  is  being  woven  into  cloth. 

Corrosion  of  the  pipes  is  not  always  due  to  acids 
in  the  water.  Chloride  of  magnesium  will  also 
cause  iron  pipes  to  rust.  It  would  be  better  and 
safer  if  all  pipes,  from  which  water  is  drawn  by  the 
"taper"  for  diluting  his  size,  were  made  of  copper. 

The  most  general  cause  of  iron-stains,  produced 
by  the  rusting  of  the  looms,  is  the  use  of  too 
small  a  proportion  of  tallow  and  too  large  a  pro- 
portion of  chloride  of  magnesium  in  the  size. 
Where  this  condition  exists  there  is  not  sufficient 
greasy  matter  present  to  protect  the  looms  from 
rusting  when  the  moisture  from  the  atmosphere 
settles  upon  the  yarn  at  night  as  the  weaving  shed 
cools.  This  moisture  will  be  more  readily  absorbed 
in  the  presence  of  a  large  proportion  of  chloride 
of  magnesium. 

I 


Iron-stains. 


537 


In  a  paper  recently  given  in  Manchester  it  was 
stated  that  the  foregoing  explanation  was  not  the  true 
cause  of  the  looms  rusting.  The  theory  was  put 
forward  that  the  rusting  was  due  to  minute  traces  of 
chlorate  of  potash,  or  chlorate  of  soda,  in  the 
chloride  of  zinc.  These  salts  are  used  for 
oxidizing  ferrous  iron  to  the  ferric  state  previous 
to  its  precipitation  as  ferric  carbonate  in  the 
manufacture  of  the  chloride  of  zinc.  This  theory  of 
chlorate  of  potash  being  the  cause  of  looms  rusting 
is  rather  a  '"far-fetched"  one.  Iron-stains  of  this 
character  occur  almost  invariably  in  "heavy"  sized 
goods,  and  generally  in  those  sized  over  100  per 
cent.  The  proportion  of  chlorate  of  potash  in  the 
chloride  of  zinc,  is,  in  the  first  place,  infinitesimal, 
therefore  the  proportion  in  the  total  "mixing"  must 
be  exceedingly  minute.  The  analysis  of  chloride  of 
zinc,  as  given  by  the  author  of  the  paper,  is  as 
follows : — 

No.  1.  No.  2. 

Chloride  of  Zinc    44*63    44*94 

Oxide  of  Zinc   0*38    1*49 

Chloride  of  Ammonium...    2 '05   absent 

Sulphate  of  Sodium   1*27    trace 

Chlorate  of  Sodium   0*28    0*31 

Water    51-39    53*26 

lOO'OO  lOO'OO 


From  this  we  may  gather  that  the  average 
amount  of  chlorate  of  soda  or  chlorate  of  potash 
is   0*3    per    cent.      As    "mixings"    increase  in 


538       The  Chemistry  and  Practice  of  Sizing. 


weight  the  proportion  of  chloride  of  zinc  decreases, 
because  the  proportion  of  flour  or  starch  decreases. 
The  following  "mixing"  gives  the  proportions  of  the 
various  ingredients  required  for   140  per  cent,  of 

size  : — 

Chloride  of  Magnesium  at  6o°  T., 

35  gallons  —    140  pounds  (solid) 

China  Clay     J792  » 

Tallow    230 

Flour  and  Starch   :   460  „ 

Chloride  of  Zinc  at  ro2°  T., 

6^  gallons  =     45      „  (solid) 

2667 

N.B. — 45  pounds  of  solid  chloride  of  zinc  is  equal  to  about 
100  pounds  of  the  ordinary  solution  at  1020  T.,  and  will  there- 
fore represent  0*3  pounds  of  chlorate  of  potash  or  soda. 

The  total  weight  of  solids  in  the  above  "mixing" 
amounts  to  nearly  2700  pounds,  and  in  this,  according 
to  the  average  analysis,  will  be  found  0*3  pounds 
(=  about  five  ounces)  of  chlorate  of  soda. 
Therefore  about  five  ounces  of  chlorate  of  soda 
will  be  mixed  with  forty-two  thousand  seven 
hundred  ounces  of  size.  To  assert  that  this  small 
quantity  of  chlorate  of  potash  or  soda  is  the 
true  cause  of  looms  rusting  is  absurd,  and  it  is 
simply  an  attempt  to  make  a  theory  fit  in  with 
established  facts.  So  small  a  proportion  of  chlorate 
of  potash  or  soda  would  be  simply  "smothered," 
and  could  not  possibly  exert  any  rusting  action  on 
the  looms. 


Iron- stains. 


539 


The  curious  part  about  this  form  of  iron-staining 
is  that  it  occurs  usually  in  the  spring  and  summer. 
This  is  actually  the  case  where  zinc,  containing 
chlorates,  is  in  use  all  the  year.  There  is  a  very 
simple  explanation  for  this.  It  is  entirely  a  question 
of  inside  and  outside  temperatures  affecting  the 
amount  of  condensation  of  moisture  in  the  weaving 
shed.  In  the  winter  the  outside  walls  and  the  glass 
are  very  cold,  and  consequently  the  moisture  in  the 
atmosphere  of  the  weaving  shed  condenses  on  the 
walls  and  glass  very  quickly.  On  the  other  hand, 
in  the  summer,  instead  of  the  condensation  taking 
place  rapidly,  and  being  localised  to  the  walls  and 
glass,  it  takes  place  gradually  during  the  night. 
The  effect  of  this  is  that  the  moisture  is  attracted 
by  the  chloride  of  magnesium,  and  settles  on  the 
looms  to  a  greater  extent  than  it  does  in  the  colder 
months  of  the  year.  If  there  be  not  a  sufficient 
quantity  of  tallow  present  in  the  size  the  moisture 
will  cause  the  iron  to  rust. 

The  reader  must  remember  that  a  manufacturer 
never  uses  excessive  proportions  of  both  chloride  of 
magnesium  and  tallow,  for  if  he  did  the  yarns  would 
be  too  "soft."  Therefore,  if  an  excessive  quantity 
of  chloride  of  magnesium  be  used,  there  is  almost 
certain  to  be  an  insufficient  quantity  of  tallow. 

Frequently  a  "mixing"  which  would  cause  the 
loom  to  rust  in  one  shed  would  not  do  so  in  another, 
and  for  this  reason  the  authors  do  not  think  it 


540      The  Chemistry  and  Practice  of  Sizing. 

desirable  to  publish  details  of  many  "  mixings" 
which  have  been  known  to  cause  iron-stains. 

There  is  one  remedy  for  these  iron-stains. 
Whenever  they  occur  the  quantity  of  tallow  used 
in  the  " mixing"  should  be  increased  and  the 
proportion  of  chloride  of  magnesium  should  be 
reduced.  The  extra  tallow  will  form  a  greasy  sur- 
face on  the  warp  and  on  the  cloth,  and  this  will 
keep  the  reeds  and  other  portions  of  the  looms  from 
rusting.    The  tallow  must  of  course  be  free  from  acid. 

Cloth  Spotted  over  with  Iron-Stains. — This 
class  of  stains  may  occur  through  many  causes. 
They  are  generally  due  to  the  presence  of  iron  in 
some  form  in  the  sizing  ingredients.  The  most  likely 
ingredients  are  the  chlorides  of  zinc,  magnesium,  and 
calcium,  or  the  water  used  for  making  the  " mixing," 
or  diluting  the  size  in  the  "sow"  box. 

It  has  already  been  mentioned  on  pages  535  and 
536  that  certain  waters  cause  iron  pipes  to  rust,  and 
if  this  rust  is  carried  into  the  size  iron-stains  are 
certain  to  form.  It  has  also  been  mentioned  on  page 
228  that  chloride  of  calcium  is  liable  to  cause  iron- 
stains  if  it  be  impure.  The  two  impurities  likely  to 
cause  these  stains  are  hypochlorite  of  calcium,  which 
acts  upon  iron  and  causes  it  to  rust,  and  chloride  of 
iron,  which  will  produce  iron-stains  of  itself.  Many 
cases  arising  from  these  sources  have  come  under 
the  writer's  notice  of  recent  years,  and  one  is 
mentioned  on  page  229. 


Iron- stains. 


54i 


Iron-stains  which  are  due  to  the  causes  mentioned 
above,  generally  develop  during  the  weaving  or 
after  the  cloth  has  been  stored  for  some  time. 

Iron-stains  are  sometimes  formed  in  the  weaving 
shed  by  water  dropping  upon  the  cloth  from  a  rusty 
iron  beam.  The  water  carries  the  iron  rust  down 
with  it,  and,  if  it  be  not  noticed  by  the  weaver,  it 
will  pass  through  several  folds  of  the  cloth,  as  it 
winds  on  the  roller.  Water  produced  by  conden- 
sation will  also  produce  iron-stains  if  it  drops  upon 
the  cloth  which  is  in  contact  with  the  iron  of  the 
loom.  The  loom  quickly  rusts  and  this  is  trans- 
ferred to  the  cloth. 

Iron-stains  are  very  often  caused  by  the  cloth 
coming  in  contact  with  oil  which  has  been  used  for 
lubricating  the  bearings  of  the  loom.  This  kind  of 
stain  is  known  as  "  black  oil  stain,"  and  will 
have  the  appearance  of  ordinary  iron -stain  when 
the  oil  is  removed,  unless  the  oil  be  taken  out 
immediately. 

TESTS  FOR  IRON-STAINS. 

1st. — Burn  a  portion  of  the  cloth  containing  the 
stain,  and  compare  the  ash  produced  with  that  ob- 
tained by  burning  an  unstained  portion  of  the  same 
size,  as  described  on  page  516.  Dissolve  each  ash 
in  dilute  hydrochloric  acid  in  separate  test  tubes,  and 
dilute  each  with  distilled  water  so  as  to  make  50  c.c. 


542       The  Chemistry  and  Practice  of  Sizing. 


of  solution.  To  each  of  the  solutions  add  two  drops 
of  ferrocyanide  of  potassium  solution.  The  ash 
containing  iron  will  give  a  deep  blue  colour, 
whilst  the  other  should  have  a  faint  blue  colour 
only. 

2nd.  —  Immerse  a  portion  of  the  stained  cloth  and 
a  portion  of  the  unstained  cloth  in  a  mixture  of 
dilute  hydrochloric  acid  and  dilute  solution  of 
ferrocyanide  of  potassium.  The  portion  showing  the 
stain  will  develop  an  intense  blue  colour  if  it  be 
due  to  iron. 

3rd. — Immerse  a  portion  of  the  stained  cloth  and 
a  portion  of  the  unstained  cloth  in  a  dilute  solution 
of  nitric  acid  and  sulphocyanide  of  potassium.  The 
stained  portion  will  develop  a  blood-red  colouration 
if  iron  be  present. 

Removal  of  Iron-Stains. — If  iron-stains  are 
caused  through  coming  in  contact  with  "black  oil" 
they  should  be  immediately  treated  with  benzene  to 
remove  the  oil  and  afterwards  treated  with  a  solution 
of  binoxalate  of  potash,  commonly  known  as  "salts 
of  lemon."  Oxalic  acid  is  frequently  used  for  this 
purpose,  but  it  is  much  more  injurious  to  the  cloth 
than  salts  of  lemon. 

If  the  iron-stain  be  a  very  fast  one  it  may  be  re- 
moved by  first  treating  it  with  dilute  hydrochloric  acid, 
and  afterwards  rubbing  it  with  a  crystal  of  sulphate 
of  copper.  These  chemicals  must  be  entirely  removed 
by  washing  the  cloth  in  clean  water  afterwards. 


Iron-stains. 


543 


"Where  "black  oil"  has  come  in  contact  with 
cloth  great  care  should  be  taken  in  removing  it, 
especially  if  the  cloth  has  to  be  bleached,  dyed,  and 
"finished/'  If  the  mineral  oil  be  not  entirely  removed 
the  bleached  cloth  will  contain  yellow  stains,  and 
if  it  be  intended  for  dyeing  the  stained  portion 
will  not  take  the  dye  properly.  See  chapter  on 
bleaching.  It  is  also  very  essential  that  every  trace 
of  oxalic  acid,  or  of  the  "salts  of  lemon,"  should  be 
washed  out  of  the  cloth,  especially  if  the  goods  are 
intended  for  bleaching.  Wherever  the  bleaching 
liquor  comes  in  contact  with  a  portion  of  the  cloth 
which  has  been  treated  with  the  above  chemicals, 
and  where  it  has  not  been  thoroughly  washed,  the 
cloth  will  be  more  or  less  tendered  through  the 
formation  of  oxycellulose. 

All  forms  of  iron-stains  which  have  been  dis- 
cussed are  due  to  manufacturers'  faults,  or  at  any 
rate,  to  the  faults  of  those  for  whom  the  manufacturer 
is  responsible.  Sometimes  cloth  becomes  iron- 
stained  through  careless  or  inferior  packing.  In 
order  to  determine  the  responsibility  in  such  a  case 
a  bale  of  the  cloth,  together  with  the  packing,  should 
be  examined  very  carefully.  The  writer  knows  many 
instances  where  the  manufacturer  has  been  held  to 
blame,  and  has  had  to  submit  to  deductions,  where 
the  stain  has  been  due  to  the  paper  used  in  packing. 

Brown  paper  always  contains  oxide  of  iron,  and 
if  this    paper    be   placed  in  direct  contact  with 


544      The  Chemistry  and  Practice  of  Sizing. 

" heavily"  sized  shirtings,  a  portion  of  the  oxide 
of  iron  is  sure  to  be  absorbed.  This  stain 
may  be  carried  through  many  folds  of  the  cloth. 
Brown  paper  should  never  be  placed  in  direct 
contact  with  the  cloth,  but  should  always  have  a 
layer  or  layers  of  white  paper  between  it  and 
the  goods. 


Bleaching, 


545 


Chapter  XV. 


Bleaching. 


Faults  in  Sized  Cloth  which  cause  Damage  when 
Bleached  and  Finished, 


HIS  chapter  has  been  written  with  the  object 


X  of  giving  cotton  manufacturers  a  clear  insight 
into  the  treatment  cloth  receives  at  the  hands  of  the 
bleacher,  and  to  show  how  damage  may  occur 
through  faults  in  sizing,  It  is  not  intended  to  be  a 
full  and  detailed  description  of  bleaching. 

The  object  of  bleaching  cotton  cloth  is  to  remove 
or  destroy  the  natural  colouring  matter  of  the  fibre 
and  render  the  fabric  white  or  colourless. 

Chemical  bleaching  has  long  superseded  the  old- 
fashioned  methods  of  subjecting  the  cotton  cloth  to 
the  action  of  light,  air,  and  moisture,  known  as 
"crofting/1 

The  principal  agents  used  for  the  chemical  bleach- 
ing of  cotton  goods  are  chlorinated  lime,  chlorinated 
soda,  slacked  lime,  soda  ash,  washing  soda  or  soda 
crystals,  caustic  soda,  soap,  and  acids,  such  as 
sulphuric,  hydrochloric,  and  acetic  acid. 


12 


546       The  Chemistry  and  Practice  of  Sizing. 


The  following  is  a  summary  of  the  usual  pro- 
cesses employed  in  bleaching  cotton  goods: — 

1.  Stamping  and  Sewing. 

2.  Singeing. 

3.  Washing  and  Steeping. 

4.  Washing  and  Limeing. 

5.  "Bowking"  or  boiling  with  milk  of  lime. 

6.  Washing. 

7.  Souring  in  Acid. 

8.  Washing. 

9.  Scouring  with  Caustic  Alkalies. 

10.  Washing. 

11.  Immersing  in  Bleaching  Liquor. 

12.  Washing. 

13.  Souring  in  Acid. 

14.  Washing. 

The  actual  method  of  carrying  out  these 
various  operations  in  a  practical  manner  will  now 
be  dealt  with  in  detail. 

THE  PRACTICAL  BLEACHING  OF 
COTTON  PIECE  GOODS. 

After  leaving  the  manufacturer  the  cloth  is  sent 
to  the  bleach  works.  Here  it  may  have  to  be  stored 
for  several  months  waiting  instructions  from  the 
merchant.  When  this  is  the  case  the  number  of 
pieces  must  be  checked  on  arrival,  and  a  few  from 


Bleaching, 


547 


each  lot  examined  for  faults.  It  is  not  always 
possible  to  examine  each  piece  separately  at  this 
stage  on  account  of  the  time  required. 

The  cloth  should  be  stored  on  stillages  in  the  grey 
room.  These  stillages  are  raised  about  six  inches 
from  the  floor  so  as  to  allow  a  free  circulation  of  air 
under  and  around  the  bundles.  Great  care  must 
be  exercised  in  the  storage  of  cotton  cloth,  as 
it  has  frequently  to  remain  in  this  position  for  a 
considerable  period.  Should  it  be  imperfectly 
stored  it  is  highly  probable  that  a  development 
of  mildew  will  take  place.  This  may  mean  con- 
siderable loss  to  the  bleacher  who  is  responsible  for 
the  cloth  whilst  in  his  charge. 

Cloth  frequently  arrives  at  the  bleach  works 
already  mildewed.  When  this  is  the  case  its  con- 
dition should  be  noted,  and  a  request  for  instructions 
sent  immediately  to  the  merchant  or  manufacturer. 
If  such  a  cloth  be  bleached  within  a  week  or  two  of 
its  arrival  there  need  be  no  fear  of  further  damage, 
as  the  mildew  growths  attack  the  starchy  matters  of 
the  size  first,  and  it  is  only  after  prolonged  contact 
that  the  cotton  fibre  is  deteriorated.  As  a  matter 
of  fact,  if  such  mildewed  cloth  be  w7ell  stored,  with 
free  access  of  air,  it  is  probable  that  the  mildew  will 
remain  dormant,  if  it  be  not  actually  destroyed. 

When  orders  are  received  the  cloth  is  taken 
from  stock  and  carefully  examined.  The  quality, 
length,   width,  and  weight,  should  be  noted,  and 


548      The  Chemistry  and  Practice  of  Sizing. 


the  number  of  threads  in  the  weft  and  warp  per 
square  quarter  inch  counted.  It  is  advisable  to  cut 
off  samples  for  reference  in  case  any  dispute  may 
arise.  The  presence  of  mineral  oil  stains  and  other 
forms  of  damage,  etc.,  should  be  carefully  looked 
for,  and  all  particulars  noted  and  entered  in 
the  "grey  book."  These  particulars  will  be 
required  in  all  the  processes  which  follow  the 
bleaching,  and  will,  if  systematically  and  correctly 
entered,  save  much  time  and  annoyance  at  a 
later  stage. 

In  order  to  carry  out  the  bleaching  operations 
successfully  it  is  essential  that  different  classes  and 
qualities  of  cloth  should  receive  treatment  according 
to  the  nature  of  the  goods,  for  instance: — 

Light  goods  require  to  be  subjected  to  less  treat- 
ment than  heavy  goods,  therefore  the  two  classes  of 
cloth  must  be  kept  separate. 

If  heavy  goods  and  light  goods  were  put  through 
the  same  treatment,  with  the  same  strength  of 
liquors,  the  latter  might  be  tendered  through 
excessive  bleaching,  or  the  former  might  be  half 
bleached  only. 

In  determining  the  treatment  in  order  to  obtain 
a  good  and  even  bleach  the  quality  of  the  cloth  must 
always  be  taken  into  consideration  also. 

Stamping  and  Stitching. — The  pieces  are 
stamped  with  the  number  assigned  to  them.  They 
are  then  conveyed  to  the  stitching  machine,  where 


Bleaching — The  Singeing  Operation.  549 


they  are  sewn  end  to  end  and  made  up  into  batches 
of  two  or  three  tons. 

Singeing. — The  operation  of  singeing  is  carried 
out  for  the  purpose  of  removing  the  short  fibres 
or  fluff  always  present  in  grey  cloth.  Should  this 
fluff  not  be  removed  the  face  of  the  cloth  will  have 
a  matted  and  raw  appearance  when  "finished," 
instead  of  having  the  gloss  which  a  perfectly  singed 
cloth  should  have. 

There  are  two  methods  of  sin^eincr  in  use  at  the 
present  time.  One  is  known  as  "the  hot  plate" 
process,  the  other  as  the  "  gas  "  singeing  process. 
In  the  former  the  machine  employed  consists 
essentially  of  two  copper  plates,  semi-circular  in 
shape,  which  are  heated  underneath  by  means  of  a 
furnace.  The  chief  objection  to  this  method  is  that 
very  often  the  plates  are  not  kept  at  a  uniform 
temperature.  If  this  occurs  the  cloth  is  unevenly 
singed  and  it  gives  a  bad  effect  when  "finished." 

The  gas  singeing  machine  is  superior  to  the 
plate  machine,  and  it  is  more  readily  prepared  for 
the  operation.  It  gives  a  more  even  singe  and  it  is 
better  adapted  for  all  classes  of  work.  This  is 
especially  the  case  where  corded  and  ribbed  cloths 
have  to  be  singed.  The  flame  is  able  to  get 
between  the  ribs,  whereas  only  the  fibre  from  the 
upper  surface  of  the  cord  would  be  removed  by  the 
plate  machine.  The  authors  would  here  point  out  the 
absolute  necessity  of  keeping  an  even  flame  on  gas 


550      The  Chemistry  and  Practice  of  Sizing, 

singeing  machines.  Many  cases  of  damaged  and 
tendered  cloth  have  been  caused  by  the  flame  being 
higher  at  one  portion  of  the  burner  than  at  another, 
thus  causing  the  gas  jet  to  impinge  more  on  one 
portion  of  the  cloth  than  on  the  other.  This  would 
scorch  and  tender  the  cloth,  more  especially  if 
chloride  of  magnesium  be  present.  The  tendering 
would  be  most  in  evidence  along  that  portion  of  the 
cloth  which  was  over-singed. 

After  the  cloth  has  been  prepared  in  the  way 
described  it  is  ready  for  bleaching. 

Steeping. — The  cloth  is  first  wet  out  with  hot 
wrater  by  passing  it  through  a  washing  machine. 
It  is  then  plaited  and  laid  out  in  a  pile  and  allowed 
to  stand  for  12  or  14  hours.  This  is  termed  the 
" rotten  steep,"  the  object  of  which  is  to  produce  a 
decomposition  in  the  starchy  matter  of  the  size,  and 
so  render  it  more  easily  removed  in  the  washing 
process  which  follows.  It  also  allows  the  chemicals 
to  act  more  readily  on  the  fibres  at  a  later  stage, 
and  prevents  the  lime  liquor  from  becoming  con- 
taminated with  size  to  the  same  extent  as  it  would 
otherwise  be. 

Washing. — At  least  two  washing  machines 
should  be  used  in  a  bleach  croft.  It  is  important 
that  each  should  have  an  abundant  supply  of  water. 
These  machines  should  be  in  a  line  between  the 
"  sour  "  and  "  chemic  "  cisterns,  and  should  be 
arranged  and  geared  so  as  to  work  conjointly, 


Bleaching —  Washing  and  Limeing.         55  r 

With  this  arrangement  the  cloth  can  be  washed 
twice  in  one  run.  It  will  be  necessary  to  fix  a 
winch  between  the  two  machines  so  that  machine 
No.  1  can  be  threaded  up,  thus  allowing  a  certain 
amount  of  slack  cloth  to  run  into  a  receptacle,  and 
enabling  it  to  be  threaded  through  machine  No.  2. 
All  draw  winches  in  a  bleach  croft  should  be 
arranged  so  that  they  are  thrown  in  or  out  of  gear 
on  starting  or  stopping  the  washing  and  liming 
machines.  If  the  winches  are  not  arranged  in  this 
way  they  will  continue  revolving,  and  this  has  a 
tendency  to  damage  the  cloth,  which  rests  upon  them, 
by  displacing  the  threads.  This  is  especially  so  in 
satin  cloths. 

It  may  be  mentioned  here  that  it  is  absolutely 
necessary  to  have  an  ample  supply  of  good  water, 
and  that  the  cloth  should  be  thoroughly  washed 
after  every  process.  This  is  specially  important 
when  the  cloth  has  reached  the  condition  of  being 
nearly  white.  It  will  be  of  advantage  to  the 
bleacher  if  he  keeps  a  memorandum  of  how  he  treats 
each  " batch"  of  cloth,  so  that  he  will  have  a  practical 
guide  in  future  operations. 

Limeing. — The  process  of  limeing  consists  of 
running  the  cloth  through  milk  of  lime  (calcium 
hydrate),  in  the  limeing  machine,  and  then  into  the 
kiers.  A  sufficient  volume  of  lime  liquor  must  be 
present  in  the  machine  box  to  ensure  a  thorough 
saturation  of  the  cloth  during  its  passage  to  the  kier. 


552       The  Chemistry  and  Practice  of  Sizing. 

"  Bowking  "  or  Boiling  with  Lime. — After  pass- 
ing through  the  limeing  machine  the  cloth  is  ready 
for  treatment  with  lime  in  the  kiers. 

In  many  bleach  works  the  kiers  are  arranged 
only  for  low  pressure  boiling,  but  high  pressure 
kiers  are  preferable  in  many  cases.  This  is 
especially  so  where  "heavy"  goods  have  to  be 
treated.  The  increase  of  temperature  of  high  pres- 
sure steam  greatly  facilitates  the  cleansing  operation. 
Low  pressure  kiers  are  the  best  for  low  qualities 
of  cloth,  as  high  pressure  steam  is  more  liable  to 
damage  a  thin  fabric.  This  also  applies  to  goods 
with  coloured  borders  and  "headings." 

All  kiers  must  be  thoroughly  lime-washed 
every  few  weeks,  first  cleaning  the  interior 
of  all  the  rust  and  dirty  matter  which  may 
have  accumulated.  The  lime-wash  may  be  more 
readily  applied  if  it  be  done  soon  after  the  kier 
has  been  emptied,  and  whilst  the  iron  is  still 
hot,  as  it  dries  and  hardens  more  quickly  under 
these  conditions.  Particular  care  should  be  taken 
that  every  portion  of  the  kier  is  covered  with 
lime.  If  any  portion  be  left  unprotected  the  cloth 
will  become  iron-stained. 

It  is  a  decided  advantage,  where  it  can  be 
arranged,  to  use  the  kiers  alternately,  first  for  lime 
boiling  and  then  for  ash  boiling. 

The  greatest  care  must  be  exercised  to  have 
sufficient  lime  liquor  in  the  kiers  to  thoroughly 


Bleaching — Boiling  with  Lime. 


553 


immerse  the  cloth  during  the  process  of  boiling,  and 
the  boiling  must  be  conducted  evenly  and  regularly. 
Boiling  milk  of  lime,  even  under  pressure,  has  no 
detrimental  action  upon  cotton  so  long  as  the  cloth 
is  entirely  immersed,  but  if  any  portion  be  exposed 
tendering  takes  place. 

In  the  case  of  strong  cloth  the  boiling  with  lime 
liquor  should  be  continued  for  at  least  six  hours  under 
a  pressure  of  30  pounds,  but  if  the  cloth  be  of  low 
quality  the  boiling  must  be  conducted  at  the  ordinary 
pressure.  After  boiling  it  should  stand  for  a  few 
hours,  care  being  taken  that  the  kier  is  filled 
with  water  so  as  to  entirely  cover  the  cloth. 
Should  this  be  neglected  and  any  portion  become 
dry,  stains  would  probably  be  developed  and  more 
or  less  tendering  take  place. 

Particular  attention  must  be  paid  to  the  manner 
in  which  the  cloth  is  plaited  down  in  the  kiers. 
It  should  be  laid  in  long  even  layers  and  not 
allowed  to  collect  in  heaps,  or  the  result  will  be  an 
uneven  bleach,  due  to  the  coils  preventing  a  free 
circulation  of  the  liquor  through  the  cloth.  In  high 
pressure  kiers  it  may  cause  the  cloth  to  be  per- 
forated or  "shot."  This  condition  is  brought  about 
by  the  steam  trying  to  force  its  way  through  the 
lumpy  places.  Many  bleachers  consider  that  these 
"shot"  holes  are  caused  during  the  "souring,"  but 
they  are  actually  formed  during  the  lime  boiling- 
process.      It  is  a  fact  that  strong  heavy  fabrics 


554      The  Chemistry  and  Practice  of  Sizing, 

are  more  affected  than  light  fabrics,  and  linen 
even  more  than  cotton.  If  the  cloth  be  properly 
arranged,  and  not  simply  dumped  into  the 
kiers,  the  steam  and  liquid  penetrates  easily 
and  thoroughly  and  "shot"  holes  are  rarely 
formed. 

It  is  important  to  remember  that  the  success  of 
bleaching,  dyeing,  printing,  and  finishing,  depends 
upon  the  cloth  being-  well  "bottomed,"  Unless  this 
condition  be  attained  the  cloth  will  not  absorb  the 
colours  properly  in  dyeing  and  printing,  and  will 
resist  the  starch  and  moisture  ("conditioning")  in 
"finishing."  The  cloth  will  also  have  a  soft  and 
greasy  feel,  with  a  creamy  tint,  instead  of  being 
white.  It  will  be  seen  therefore,  how  much  the 
success  of  the  after  processes  depends  upon  the 
thoroughness  of  the  boiling. 

After  being  boiled  in  the  kier  the  cloth  must 
be  thoroughly  washed  again,  and  afterwards  con- 
ducted to  the  cisterns  to  be  treated  with  acid,  i.e., 
the  "souring"  process. 

"Souring," — In  this  operation  the  cloth  is 
treated  with  dilute  hydrochloric  acid  (spirits  of 
salts)  or  sulphuric  acid  (vitriol).  The  "souring" 
at  this  stage  being  known  as  the  "grey  sour,"  The 
operation  should  be  conducted  in  stone  cisterns. 

The  acid  solution,  known  as  "sours,"  is  made 
to  Twaddell  at  about  one  to  three  degrees,  accord- 
ing to  the  quality  of  the  cloth.    A  strong  cloth 


Bleaching — ^  Souring."  555 


resists  the  acid  more  than  one  of  a  low  grade. 
The  acid  solution  is  prepared  beforehand  in  a 
cistern  underneath  that  containing  the  cloth  and 
it  is  sprinkled  over  the  cloth  by  means  of 
a  centrifugal  pump  and  a  rose  sprinkler.  The 
pipe  leading  from  the  pump  must  be  made  of  lead, 
as  this  metal  is  not  acted  upon  by  weak  acids. 
The  same  metal  is  also  used  for  the  solution  of 
"chemic."  It  is  necessary,  of  course,  to  have 
separate  pumps  for  the  acid  and  "  chemic"  solutions. 

In  mixing  the  "sours"  it  is  advisable  to  dilute  the 
strong  acid  with  about  twice  its  volume  of  water.  It 
will  then  be  found  to  mix  in  the  "sour"  much  better. 

Whenever  it  is  required  to  dilute  sulphuric  acid 
the  acid  should  be  poured  slowly  into  the  water  and 
agitated.  Water  should  never  be  poured  into  strong 
sulphuric  acid. 

Some  bleachers  prefer  sulphuric  acid  (vitriol) 
solution  as  a  "sour,"  but  it  has  certain  objectionable 
features  which  hydrochloric  acid  has  not.  It  is 
hardly  possible  to  remove  the  whole  of  the  lime 
introduced  into  the  cloth  in  the  previous  operation 
by  washing,  and  should  any  be  left  in  the  fabric, 
the  sulphuric  acid  will  convert  it  into  sulphate  of  lime. 
This  substance  is  developed  within  the  fibre  itself, 
and  being  almost  insoluble,  it  is  nearly  impossible  to 
remove  it  afterwards. 

Sulphate  of  lime  will  cause  stains,  known  as  lime- 
stains,  to  be  formed.    These  patches  of  sulphate  of 


556       The  Chemistry  and  Practice  of  Sizing, 

lime,  besides  causing  the  cloth  to  have  a  harsh  feel, 
will  be  detrimental  in  the  later  processes  of  dyeing 
and  printing.  Hydrochloric  acid  14 sour"  has  no  such 
objectionable  property.  This  acid  forms  a  soluble 
salt  of  lime  which  is  very  easily  removed  by 
washing. 

Another  method  of  "souring,"  sometimes  em- 
ployed, is  to  pass  the  cloth  through  one  of  the 
washing  machines  containing  acid  liquor.  A  pipe  is 
fixed  to  the  machine  and  this  is  connected  with  a 
cistern  containing  the  '"sours."  The  box  of  the 
machine  should  be  kept  well  filled  with  the  " sours" 
until  the  process  is  completed.  The  cloth  is  plaited 
into  a  pile  as  it  leaves  the  machine,  or  it  is  conducted 
to  a  stone  cistern  where  it  is  allowed  to  stand  from 
one  to  four  hours.  This  process  clears  the  cloth  of 
the  lime  and  all  superfluous  matter  which  may  remain 
in  it  after  limeing. 

Grey  limeing  and  "souring"  must  be  thoroughly 
conducted.  Careful  attention  to  details  is  amply 
repaid  at  a  later  stage. 

After  "grey  souring"  the  cloth  should  be 
thoroughly  washed  through  the  washing  machines 
and  squeezed  as  dry  as  possible.  The  reason  for 
this  is,  that  if  the  cloth  contained  a  large  quantity 
of  moisture  it  would  dilute  the  soda  ash  liquor  in 
the  next  process.  After  washing  and  squeezing,  the 
cloth  is  taken  to  the  ''ash  kier"  for  treatment  with 
soda  ash. 


Bleaching — '  'Soda  A  sh  Boil"  and  "Chemicking."  557 

Soda  Ash  Boil, — -In  this  operation  the  cloth 
is  placed  in  the  kier  and  carefully  and  evenly 
arranged.  This  is  done,  as  a  rule,  by  boys.  It  is 
necessary  that  the  clogs  worn  by  the  boys  should 
not  have  the  usual  irons  on  the  soles,  nor  should 
there  be  any  iron  nails  used  in  their  construction. 
Brass  nails  are  not  objectionable. 

For  strong  and  "heavy"  goods  3  pounds  of 
soda  ash  will  be  required  for  each  112  pounds  of 
cloth.  For  low  qualities  \\  pounds  will  be  sufficient, 
At  this  stacre  it  will  be  found  beneficial  to  use  resin 

o 

soap  in  the  proportion  of  about  \  per  cent,  of  the 
weight  of  cloth.  This  soap  not  only  cleanses 
efficiently  but  it  greatly  facilitates  the  " finishing." 

The  cloth  is  boiled  for  the  same  length  of  time 
and  under  the  same  conditions  as  described  under 
lime  boiling  on  page  553.  It  is  then  allowed  to 
stand  in  the  solution  for  about  eight  hours  ;  the 
same  precautions  being  taken  again  to  fill  up  the 
kier  with  boiling  water.  The  cloth  is  then 
thoroughly  washed  and  run  into  a  stone  cistern, 
where  it  is  impregnated  with  a  solution  of  bleaching 
powder  (Mchemic"). 

"Chemicking." — In  this  operation,  the  cloth  is 
treated  with  a  solution  of  bleaching  powder.  The 
cloth  must  be  thoroughly  immersed  in  the  solution, 
and  the  sprinklers  kept  constantly  working.  Should 
any  portion  of  the  cloth  be  exposed  to  the  atmosphere 
during  this  operation  it  will  be  made  whiter  than 


558      The  Chemistry  and  Practice  of  Sizing. 

that  unexposed.  This  is  due  to  the  quicker  liberation 
of  hypochlorous  acid  from  the  "chemic,"  brought 
about  by  the  action  of  atmospheric  carbon  dioxide 
and  light. 

The  bleaching  liquor  should  be  made  of  a  strength 
Twaddelling  about  \\  to  2\  degrees,  the  bleacher 
here  using  his  own  judgment  as  to  the  particular 
strength  necessary  for  the  class  of  cloth  he  may 
be  treating.  It  is  found  that  cloth  made  from 
Egyptian  cotton  requires  a  stronger  liquor  than  that 
made  from  American  cotton. 

The  cloth  should  remain  in  the  "chemic"  for  about 
four  hours.  It  is  then  well  washed  and  afterwards 
run  into  the  "sour"  cisterns  to  undergo  treatment 
with  acid  once  again.  If  the  cloth  be  intended  for 
dyeing  or  printing,  hydrochloric  acid,  Twaddelling 
\\  to  2  degrees,  should  be  used.  It  should  remain 
immersed  in  a  liquor  of  this  strength  from  three 
to  four  hours,  after  which  it  should  be  thoroughly 
washed.  The  cloth  is  then  ready  for  the  squeezing 
machine. 

"PURE"  WHITE  GOODS. 

If  the  cloth  be  intended  for  ''pure"  white  goods 
it  will  have  to  undergo  further  treatment.  It  will 
be  necessary  to  boil  again  in  the  4 'ash  kiers"  with 
a  further  quantity  of  soda  ash,  after  which  it  should 
be  washed,  re-chemicked,  washed  again,  and 
afterwards  "white  soured."   In  this  "souring,"  weak 


Bleaching — "Pure  Whites." 


559 


sulphuric  acid  is  used.  This  should  not  exceed  one 
degree  in  strength  as  shown  by  the  Twaddell's 
hydrometer.  The  "ash'^  and  bleaching  liquors 
should  be  much  weaker  than  those  used  in  the 
first  treatment,  as  this  latter  process  is  required  only 
as  a  final  clearing.  It  will  also  be  found  advan- 
tageous to  use  a  small  quantity  of  soft  soap  during 
the  boiling  in  soda  ash. 

After  " white  souring"  the  cloth  is  ready  for 
the  final  wash,  and  this  must  be  thoroughly  done. 
No  possible  injury  can  occur  to  the  fabric  by  the 
various  washings,  and  each  one  further  cleanses  it. 

After  washing  out  the  " white  sours"  it  is 
advisable  to  pass  the  cloth  through  a  weak  solution 
of  ammonia  contained  in  the  squeezing  machine. 
This  will  neutralise  any  remaining  trace  of  acid,  es- 
pecially in  "heavy  "  goods  from  which  the  acid  is  not 
entirely  removed.  Should  any  free  acid  be  left  the 
cloth  will  be  tendered  on  drying. 

A  little  ultramarine  blue  may  be  mixed  with  the 
ammonia  solution,  care  being  taken  that  the  liquor  is 
not  "  blued "  too  much,  for  if  this  is  the  case  the  cloth 
will  be  streaky.  This  effect  is  caused  on  account 
of  the  cloth  being  squeezed  in  the  form  of  a  rope. 
It  should  be  left  to  the  "finisher"  to  produce  the 
right  shade  or  tint. 

After  squeezing,  the  cloth  is  ready  for  the  "white 
mangle,"  which  should  have  a  scutching  machine 
attached  to  it. 


560      The  Chemistry  and  Practice  of  Sizing. 

Cloth  which  is  intended  for  "whites-"  or  for 
printing  should  be  dried  as  soon  as  possible 
and  stored  in  a  cool  dry  place.  If  left  wet  for  any 
length  of  time  it  will  become  "  weather  struck,''  and 
turn  yellow,  this  being  due  to  some  parts  of  the 
cloth  drying  more  slowly  than  others.  If  the 
cloth  is  for  dyeing  it  can  be  made  into  suitable 
"batches"  and  left  in  the  wet  state,  it  being  un- 
necessary in  this  case  to  dry  after  mangling. 

CAUSTIC  SODA  PROCESS  OF 
BLEACHING. 

This  process  consists  of  boiling  the  cloth  in  a 
solution  of  caustic  soda  instead  of  in  lime  (milk  of 
lime)  and  soda  ash.  The  process  will  be  found  to 
answer  very  well  where  the  cloth  is  for  printing  and 
dyeing.  It  is  important  that  a  fair  amount  of  resin 
soap  should  be  used  in  this  process,  otherwise  the 
cloth  will  turn  up  very  soft  and  greasy  when 
"finished."  The  following  is  the  method  of 
procedure : — 

After  singeing,  the  cloth  is  allowed  to  steep  as 
previously  described  on  page  550.  It  is  then  boiled 
for  six  hours  in  a  solution  of  caustic  soda  and  resin 
soap.  For  ordinary  qualities  of  cloth  a  solution  of 
caustic  soda  Twaddelling  3  degrees  may  be  used, 
but  for  low  qualities  of  cloth  a  weaker  solution 
should  be  used.     For  each   100  pounds  of  cloth 


Bleaching — Scouring  Operation.  561 


three-quarters  of  a  pound  of  resin  soap  should  be 
added. 

After  boiling,  the  cloth  is  allowed  to  steep  in  the 
liquor  as  described  on  page  353,  and  afterwards 
well  washed.  It  is  then  "soured"  with  hydrochloric 
acid,  washed,  and  again  boiled  for  six  hours  in  a 
solution  of  caustic  soda  Twaddellinor  about  1  to  2 
degrees.  After  boiling,  the  cloth  is  again  allowed 
to  steep  as  before,  then  well  washed,  and  finally 
treated  with  bleaching  liquor  Twaddelling  \\  to  2\ 
degrees.  The  cloth  should  lie  in  this  liquor  from 
two  to  four  hours,  the  sprinklers  being  kept  working 
during  this  time. 

After  "  chemicking,"  the  cloth  is  again  well 
washed,  then  "soured"  with  the  "white  sour" 
(sulphuric  acid)  Twaddelling  about  1  to  2  degrees, 
and  allowed  to  lie  as  previously  described.  It  is 
then  well  washed,  after  which  it  is  ready  for 
squeezing,  scutching,  and  mangling. 

THE  "SCOURING"  OF  COTTON 
GOODS. 

This  process  is  carried  out  where  cloth  has  after- 
wards to  be  dyed  some  dark  shade  as  in  the  case  of 
aniline  black.  In  preparing  what  are  known  as 
"scoured"  or  "half-bleached"  goods  the  following 
procedure  is  adopted  : — 

The  methods  described  on  page  547  and  the 
following  pages,  up  to,  and  including  the  process  of 

J2 


562      The  Chemistry  and  Practice  of  Sizing. 

boiling  in  soda  ash,  are  carried  out,  using  the  same 
strength  of  liquors.  At  each  of  the  stages  of  steep- 
ing and  boiling  the  methods  of  procedure  are  the 
same. 

After  the  cloth  has  been  boiled  in  the  soda  ash 
kier  and  steeped,  it  should  be  well  washed  and 
run  into  the  '"sour"  cistern,  where  it  undergoes  a 
" souring"  with  hydrochloric  acid,  Twaddelling  3 
degrees.  The  cloth  is  then  well  washed  to  remove 
all  traces  of  acid.    This  completes  the  process. 

It  is  the  custom  of  some  bleachers  not  to  "sour" 
after  boiling  in  the  soda  ash.  They  prefer,  after 
washing  out  the  "ash,"  to  take  the  cloth  right  to  the 
squeezer.  This  is  not  a  good  method  as  it  will  be 
found  that  " souring"  at  this  stage  materially  helps 
to  whiten  the  cloth,  and  will  be  of  advantage  both  to 
the  bleacher  and  the  finisher. 

OPEN  BLEACHING, 

OR  THE  MANIPULATION  OF  THE  CLOTH   IN  THE 
OPEN  WIDTH, 

The  process  of  "open  bleaching,"  where  it  can 
be  adopted,  is  desirable  for  certain  classes  of  goods 
in  which  the  face  of  the  cloth  is  liable  to  become 
damaged  in  passing  through  the  various  machines 
in  the  rope  form.  This  is  the  case  with  such  cloths 
as  satins,  satteens,  flannelettes,  piques,  "bedford" 
cords,  brocades,  etc. 


Bleaching — The  "Open'  Process.  563 


There  are  many  machines  on  the  market  for 
this  method  of  bleaching,  but  the  procedure  is 
practically  the  same  in  every  case,  and  may  be 
summarised  as  follows  : — Sorting,  Stamping,  Sew- 
ing, Singeing,  Washing  in  Steep,  Running  through 
Boiling  Caustic  Soda  Liquor,  Steeping,  Washing, 
Souring,  Washing,  Chemicking,  Washing,  Souring, 
and  the  final  Wash.  The  strength  of  the  liquors 
varies  according  to  the  kiers  used,  and  to  the 
quality  of  the  cloth  to  be  treated.  The  experience 
gained  by  following  out  the  instructions  given  in  the 
preceding  pages  will  be  sufficient  to  enable  the 
practical  reader  to  carry  out  the  processes. 

GENERAL  INSTRUCTIONS. 

In  carrying  out  the  bleaching  operations  the 
following  essential  precautions  should  be  observed  : — 

(1)  Care  must  be  taken  that  the  cloth  does  not 
get  splashed  with  bleaching  liquor  or  mineral  acid 
"sours,"  especially  vitriol,  as  these  liquids  have  a 
tendency  to  produce  white  spots  in  the  fabric,  espec- 
ially in  " scoured"  goods. 

(2)  Care  must  be  taken  that  the  cloth  is  not  sub- 
jected to  any  undue  strain  in  its  various  movements 
during  the  different  processes,  as  this  will  cause 
such  cloths  as  drills,  satins,  sateens,  etc.,  to  crack 
on  the  selvedges.  This  is  much  more  the  case  with 
these  than  with  ordinary  plain  cloth.    The  tension 


564      The  Chemistry  and  Practice  of  Sizing. 

must  therefore  be  watched  and  regulated  so  as  to 
avoid  any  undue  strain. 

(3)  In  the  case  of  lawns,  handkerchiefs,  and 
other  very  light  goods,  it  is  better  to  hand  "scutch" 
than  to  employ  a  "scutching"  machine.  In  the 
former  operation  the  headings  and  borders  are  kept 
much  straighter  and  there  is  not  the  same  risk  of 
damage  as  when  the  machine  is  used. 

In  conclusion  the  authors  would  again  point  out 
that  there  is  only  one  way  to  ensure  success  in 
bleaching,  and  that  is  by  thoroughly  "bottoming"  the 
cloth  in  the  boiling  operations.  Any  attempt  to 
shorten  the  operations  cannot  meet  with  success.  A 
good  many  bleachers  have  tried  to  obtain  good 
whites  by  using  stronger  "chemic"  and  boiling  less 
but  with  one  result  only,  i.e.,  bad  work.  The  cloth 
may  look  white  at  first  but  when  it  is  kept  for  some 
time  it  begins  to  come  up  brown  or  yellow. 

THE  BLEACHING  OF  COTTON  GOODS 
Woven  with  Coloured  Borders 
and  Headings. 

Dhooties,  towels,  handkerchiefs,  and  other  cotton 
goods  which  are  woven  with  coloured  borders  and 
headings  have  frequently  to  be  bleached.  They 
require  more  careful  treatment  than  ordinary  whites 
and  prints,  and  they  are  very  often  damaged  in  the 
course  of  bleaching. 


Bleaching — ''Coloured  Borders."  565 


The  coloured  yarns  used  in  the  manufacture 
of  such  cloth  should  be  dyed  with  materials  capable 
of  withstanding  the  bleach,  otherwise  the  colours  will 
be  damaged  or  entirely  destroyed.  Cases  re- 
peatedly come  under  the  writer's  notice  in  which 
coloured  yarns  have  been  used,  especially  for  the 
headings,  which  have  been  utterly  unfit  for  the 
purpose.  In  some  instances  this  has  been  clue  to 
carelessness  or  lack  of  knowledge  on  the  part  of  the 
manufacturer,  whilst  in  other  cases  it  has  been  due 
to  being  misled  by  the  dyers  of  the  yarn. 

The  chief  colours  which  may  be  satisfactorily 
employed  to  stand  bleaching  are  the  following: — 

1.  Red — Alizarine  Red 

2.  Pink — Alizarine  Pink 

3.  Orange — Alizarine  Orange 

4.  Yellow — Alizarine  Yellow 

5.  Chocolate — Alizarine  Chocolate 

6.  Purple — Alizarine  Purple 

7.  Heliotrope — Alizarine  Heliotrope 

8.  Buff — Catechu  or  Cutch 

9.  Brown —  do.  do. 

10.  Blue — Indigo 

11.  Black — Aniline  Black 

The  Indanthrene  Series  of  Colours. — The 
indanthrene  colours  are  a  new  series  of  colours 
which  have  been  introduced  recently.  Indanthrene 
(blue)  is  employed  as  a  substitute  for  Indigo. 
Mixtures  of  indanthrene  and  flavanthrene  produce 
various  shades  of  green.  The  indanthrene  colours 
have  been  much  improved  recently  and  they  are 


566       The  Chemistry  and  Practice  of  Sizing. 


being  successfully  used  at  the  present  time  for 
headings  and  borders.  The  very  greatest  care  has 
to  be  exercised,  however,  in  the  bleaching,  otherwise 
they  bleed  and  4 'mark  off,"  and  no  process  can 
remove  the  stains,  after  they  have  once  formed, 
without  destroying  the  fabric.  It  is  in  the  kier 
w7here  the  damage  is  done.  Indanthrene  colours 
should  not  be  boiled,  the  temperature  of  the  alkaline 
liquor  being  kept  below  200°  Fah.  Some  of  the 
colours  will  not  stand  even  this  temperature.  Soda 
crystals  should  be  employed  in  place  of  soda  ash,  as 
even  a  trace  of  free  caustic  alkali  will  cause"  bleeding." 
All  the  bleaching  operations  should  be  carried 
out  with  weaker  solutions  than  those  used  for  the 
alizarines,  indigo,  etc.,  as  given  on  pages  573  and  574. 

If  indanthrene  colours  "pale"  as  the  result  of 
"chemicking,"  they  may  be  restored  by  treatment 
with  a  reducing  agent  such  as  a  solution  of  tin 
crystals  or  titanous  chloride  in  acid  solution. 

Direct  and  basic  dyes  should  on  no  account  be 
used  for  yarns  which  have  to  be  subjected  to  bleach- 
ing, nor  should  mineral  dyes  such  as  chrome  yellow 
or  chrome  orange  be  employed  unless  the  cloth 
be  subjected  to  special  treatment. 

Unfortunately,  it  is  the  practice  of  many  dyers  to 
obtain  the  desired  shade  by  ''topping"  (i.e.,  by 
applying  a  basic  dye  to  the  original  colour  after  the 
first  bath).  By  this  means  they  obtain  brightness  and 
intensity  of  shade  at  a  less  cost  and  with  a  smaller 


Bleaching — ' 1  Coloured  Borders. "  567 


amount  of  the  proper  colour.  Thus,  alizarine  red  is 
frequently  "topped  "with  ;/z<^#/#,  alizarine  purple  with 
violet,  alizarine  yellow  and  orange  with  auramine,  buff 
and  brown  with  Bismarck,  indigo  blue  with  a  direct 
blue,  and  aniline  black  with  logzvood  and  direct  black. 
In  fact,  the  authors  know  of  cases  where  logwood 
and  direct  black  have  been  substituted  entirely  for 
aniline  black. 

Where  such  "topping,"  or  entire  substitution 
takes  place,  the  colours  are  sure  to  suffer  in  the 
bleaching  processes.  It  is  therefore  to  the  interest 
of  both  manufacturer  and  bleacher  that  the  colours 
should  be  carefully  tested  before  proceeding  with 
the  manufacture  or  bleaching  of  the  cloth.  By 
taking  this  precaution  damage  and  subsequent  dis- 
putes would  be  avoided  and  the  bleacher  particularly 
would  be  safeguarded  against  responsibility  for 
spoiled  cloth.  It  would  be  very  difficult  to  place 
the  responsibility  after  the  goods  have  been  bleached, 
especially  where  the  dyes  have  been  "topped"  and 
not  altogether  substituted,  In  such  a  case  an 
analysis  would  show  that  the  correct  colour  had  been 
used  (the  colour  used  for  "topping"  having  been 
destroyed  in  the  bleach),  and  the  probability  would 
be,  in  case  of  dispute,  that  the  dyer  would  assert 
that  the  goods  had  been  improperly  treated.  It  will 
be  readily  seen  therefore,  that  unless  the  bleacher 
takes  the  precaution  to  keep  a  sample  of  the 
unbleached  cloth,  as    directed  on  page    548,  he 


568       The  Chemistry  and  Practice  of  Sizing. 


would  probably  be  held  liable  for  damage  caused 
through  no  fault  of  his  own. 

Should  the  tests  for  the  colours  be  applied  as 
here  directed,  and  basic,  or  direct,  or  other  ob- 
jectionable colours  be  found,  the  bleacher  should 
at  once  give  notice  to  the  manufacturer  or  merchant 
before  proceeding  further,  thus  clearing  himself  of 
all  responsibility  for  the  results. 

Damaged  headings  are  also  frequently  caused  by 
manufacturers  using  cops  of  weft  of  the  right 
shade,  but  dyed  with  unsuitable  dyes  for  bleach- 
ing, along  with  coloured  weft  which  will  stand 
the  bleaching.  The  result  is  that  one  portion  of  the 
coloured  heading  is  destroyed  whilst  the  other 
remains  alright. 

Tests  to  be  applied  to  determine  the  Dyes  on 
Coloured  Borders  and  Headings. 

(1)  Test  for  Presence  of  Basic  Dyes  on 
Alizarine. — -Treat  a  small  portion  of  the  coloured 
border  with  acetic  acid,  and  press  between  white 
blotting  paper.  If  any  basic  colour  has  been  used 
a  distinct  colouration  will  be  apparent  on  the  blotting 
paper. 

(2)  Test  for  Primuline  Red. — Treat  a  portion 
of  the  coloured  border  with  solution  of  titanous 
chloride  in  hydrochloric  acid.  This  will  discharge 
the  colour.  Diazotise  and  re-develop  with  beta- 
naptholate  of  soda. 


Bleaching — "  Coloured  Borders!'  569 


(3)  Test  for  Presence  of  Direct  Blue  on 
Indigo. — Treat  a  portion  of  the  coloured  border 
with  nitric  acid.  This  will  discharge  the  indigo, 
leaving  a  buff  stain  surrounded  by  a  green  colour- 
ation. If  this  test  be  carefully  watched  any  direct 
blue  which  may  be  present  is  detected  by  the 
production  of  a  reddish  stain.  This  stain  takes 
longer  to  discharge  than  pure  indigo.  Should  the 
red  stain  appear,  treat  another  portion  of  the  dyed 
border  with  a  weak  solution  of  bleaching  powder. 
This  will  discharge  the  direct  colour,  leaving  the 
indigo.  If  this  portion  be  then  well  washed  and 
treated  with  nitric  acid,  the  indigo  will  be  discharged 
without  the  production  of  the  reddish  stain. 

The  nitric  acid  should  be  made  by  mixing  three 
parts  of  water  with  seven  parts  of  strong  nitric  acid. 

(4)  Test  for  Indanthrene  Blue. — Treat  a  por- 
tion of  the  coloured  border  with  strong  nitric  acid. 
The  colour  is  discharged  as  in  the  case  of  indigo,  but 
may  be  restored  by  means  of  a  solution  of  titanous 
chloride.     Indigo  is  not  restored  by  this  treatment. 

(5)  Test  for  Presence  of  Logwood  Dye. — 
Treat  a  portion  of  the  coloured  border  with 
hydrochloric  acid,  a  bright  red  stain  indicates 
logwood. 

(6)  Test  for  Direct  Black  on  Aniline 
Black. — Treat  the  coloured  border  with  a  strong  cold 
solution  of  bleaching  liquor.  If  direct  black  has  been 
used  it  is  identified  by  the  formation  of  a  heavy  buff 


570      The  Chemistry  and  Practice  of  Sizing. 

stain.  If  the  colour  be  a  pure  aniline  black  the  strong 
bleaching  liquor  changes  it  but  slightly,  forming  a 
greenish  black. 

Sometimes  yarns  which  are  sold  as  " aniline 
black"  are  "topped"  with  a  basic  colour.  This 
leads  to  damage  when  the  goods  are  bleached. 
Very  often  the  basic  colour  will  mark  off,  especially 
if  the  fabric  be  subjected  to  pressure. 

The  presence  of  a  basic  dye  on  aniline  black 
may  be  detected  by  means  of  acetic  acid,  as 
described  on  page  568, 

A  yarn  may  be  dyed  with  aniline  black  and  yet 
unsuitable  for  bleaching  purposes.  There  are  two 
processes  of  aniline  black  dying  recognised  in 
commerce.  One  is  known  as  the  "aged  aniline 
black  process,"  and  the  other  as  the  "one  bath 
process."  In  the  former  process  the  dye  is  faster 
because  it  has  impregnated  the  fibre  itself,  whereas 
in  the  latter  process  the  dye  is  more  or  less  on  the 
outside  of  the  fibre.  In  the  first  case,  the  yarn  is 
suitable  for  bleaching,  but  in  the  second  case  it  will 
not  stand  the  process.  It  is  important  therefore  that 
the  manufacturer  should  state  definitely,  when  order- 
ing black  yarn,  that  it  is  intended  to  be  woven  into 
cloth  which  has  to  be  bleached,  otherwise  damage  is 
certain  to  occur.  This  damage  may  take  the  form 
of  mauve  or  buff  stains  on  the  white  cloth,  due  to  the 
oxidation  of  the  loose  dye  which  has  marked  off  and 
become  oxidised  by  the  chemic  liquor. 


Bleach  ing — ' '  Coloured  Borders. "  571 


The  oxidised  aniline  black  stain  can  be  extracted 
from  the  cloth  by  means  of  alcohol,  and  this  may  be 
turned  to  account  as  a  test  for  aniline  black  which 
has  been  dyed  by  the  "one  bath"  process.  The 
solution  of  dye  should  be  diluted  with  water  and  the 
alcohol  boiled  off.  Two  pieces  of  cotton  cloth,  one 
mordanted  with  tannin,  and  the  other  unmordanted 
should  be  dipped  into  the  solution.  Both  pieces  will 
take  the  dye,  but  the  one  not  mordanted  can  be 
"cleared"  by  washing  in  cold  water,  whereas  the 
other  is  fast  to  this  treatment. 

In  cases  where  a  stain  is  black  and  it  is  suspected 
to  be  aniline  black  it  should  be  tested  by  treating  the 
cloth  to  a  hot  solution  of  chemic.  This  treatment 
converts  the  black  into  a  buff  or  mauve  stain  which 
can  be  tested  as  previously  described. 

A  case  of  marking-off  came  under  the  writer's 
notice  a  short  time  ago.  The  cloth  which  had  been 
damaged  contained  a  heavy  Turkey-red  heading. 
A  number  of  black  threads  formed  a  border  to  this 
heading,  and  these  threads  had  marked  off  when 
the  cloth  was  "beetled."  That  the  damage  was  not 
due  to  over-bleaching  was  apparent,  as  the  cloth  had 
a  pink  shade  instead  of  being  white.  The  pink 
shade  was  due  to  the  bleeding  of  the  Turkey  red. 
An  analysis  of  the  stain  showed  that  the  aniline 
black  had  been  produced  in  the  "one-bath  process," 
and  the  manufacturer  was  to  blame  for  using-  an 
inferior  and  unsuitable  yarn. 


572      The  Chemistry  and  Practice  of  Sizing. 

(7)  Test  for  Sulphur  Colours. — Boil  a 
portion  of  the  coloured  border  with  water  and 
hydrochloric  acid  in  a  suitable  beaker,  and  test 
the  escaping  steam  by  means  of  lead  acetate 
paper.  In  the  presence  of  sulphur  colours  this 
will  blacken,  due  to  the  formation  of  sulphide 
of  lead  by  the  sulphuretted  hydrogen  which  is 
liberated. 

Sulphur  colours  are  very  fast  to  light  and  to 
washing,  but  they  are  not  suitable  for  goods  which 
have  to  be  bleached. 

(8)  Tests  for  Orange  Cfirome  (Oxychromate 
of  Lead)  and  Yellow  Chrome  (Chromate  of 
Lead)  Dyes. — Treat  the  orange  or  yellowr  border 
with  dilute  hydrochloric  acid.  The  colours  rapidly 
disappear,  the  orange  passing  through  various  shades 
of  yellow,  until  it  is  entirely  discharged,  whilst  the 
yellow  is  rapidly  destroyed.  In  each  case  a  colour- 
less substance,  chloride  of  lead,  is  formed.  The 
presence  of  the  lead  salt  may  be  determined  by 
adding  to  the  discharged  portion  of  the  border  a  few 
drops  of  a  solution  of  sulphuretted  hydrogen,  or 
sulphide  of  ammonium.  A  black  stain  is  produced 
if  lead  be  present. 

A  peculiar  and  most  interesting  case  of  damage, 
due  to  the  use  of  orange  chrome  dyed  yarns  in 
conjunction  with  yarns  dyed  with  Turkey  orange, 
came  under  the  writer's  notice  a  few  years  ago. 
Details  of  this  are  given  on  page  575. 


Bleaching — "  Coloured  Borders. "  573 


THE  PRACTICAL  BLEACHING  OF 
COTTON  GOODS  WITH 
COLOURED  BORDERS  AND  HEADINGS. 

The  goods  are  first  examined  and  sorted,  as 
described  on  page  546.  They  are  then  stamped 
with  the  respective  numbers  and  those  which  require 
" singeing"  are  put  through  that  process.  The  cloth 
is  then  "wet  out"  with  hot  water,  and  allowed  to 
stand  for  about  ten  hours,  after  which  it  is  washed. 
It  is  then  run  into  the  kier,  which  should  be 
wTorked  under  ordinary  pressure,  and  boiled  for 
about  eight  hours  with  a  liquor  containing  the 
following  ingredients  to  each  112  lbs.  of  cloth: — 

Soda  Ash    1  pound. 

Soft  Soap    h  „ 

The  soda  ash  must  be  free  from  caustic  soda  or  lime 
as  these  substances  will  more  or  less  alter  or  destroy 
the  colours,  especially  in  the  case  of  the  alizarines, 
and  the  indanthrene  series.  After  boiling,  the  cloth 
is  well  washed  through  the  washing  machine.  It  is 
then  run  into  the  "souring"  cistern,  where  it  is 
immersed  in  a  "sour"  of  weak  vitriol  (sulphuric 
acid),  for  about  two  hours.  The  "sours"  should 
not  be  stronger  than  £°  T.  From  this  "sour"  it  is 
well  washed,  and  again  boiled  for  about  eight  hours 
in  soda  ash  and  soap  as  before,  using  three-quarters- 
of-a-pound  of  soda,  and  half-a-pound  of  soap,  to 
each  112  pounds  of  cloth.    The  cloth  is  again  well 


574      The  Chemistry  and  Practice  of  Sizing. 

washed,  after  which  it  is  run  into  the  "chemic" 
cisterns,  where  it  is  immersed  in  a  weak  solution  of 
bleaching  liquor  for  about  four  hours.  The  bleaching 
liquor  should  not  be  stronger  than  |°  T.  It  is  most 
essential  that  the  cloth  should  be  entirely  covered 
with  the  bleaching  liquor,  for  if  any  part  be  exposed 
to  the  atmosphere  the  "chemic"  will  be  more  active 
in  its  bleaching  powers,  and  the  coloured  borders 
will  be  paler  in  that  portion  exposed  than  in  that 
which  has  been  covered. 

At  this  stage  the  bleacher  must  give  the  cloth 
the  greatest  attention.  It  is  necessary  to  constantly 
examine  the  colours  to  see  that  the  process  of 
" whitening"  is  not  carried  too  far,  otherwise  he  will 
have  "pale  colours/' 

After  "chemicking,"  the  cloth  is  again  well 
washed,  and  instead  of  ''souring"  in  acid  it  should 
be  run  into  a  solution  of  thiosulphate  of  soda 
(hyposulphite-antichlor),  containing  two  ounces  to 
each  gallon  of  water.  The  cloth  is  allowed  to 
stand  for  two  hours  in  this  solution.  It  is  then 
finally  washed  and  sent  to  the  squeezing  machine. 

The  reason  the  authors  advocate  the  use  of  thio- 
sulphate of  soda,  instead  of  an  acid  "sour/'  is  that 
acid  frequently  causes  the  colours  of  the  borders  and 
headings  to  "mark  off'  and  produces  stains  on  the 
white  portion  of  the  cloth.  One  case  of  this  kind 
is  described  on  page  575,  whilst  another  is  described 
on  pages  578  and  579. 


Bleaching — ' '  Coloured  Borders, "  575 


About  a  yard-and-a-half  of  a  Turkey  orange 
bordered  dhootie  was  submitted  for  analysis.  On 
examination  the  cloth  was  found  to  be  tinted  through- 
out  with  a  pink  shade  instead  of  being  pure  white. 
The  experiment  was  tried  of  "souring"  it  with  dilute 
hydrochloric  acid,  and  the  colour  was  immediately 
discharged,  leaving  the  fabric  white.  In  this  case 
it  was  evident  that  the  bleacher  had  omitted  to 
clear  the  fabric  from  the  chemic,  either  by  "souring," 
or  by  use  of  "antichlor,"  but  had  simply  washed 
after  chemicking.  It  was  also  evident  that  the 
washing  had  been  superficial,  otherwise  the  chemic 
would  not  have  been  present  in  sufficient  quantity 
to  discharge  the  colour  on  treatment  with 
dilute  acid. 

With  the  evidence  obtained  the  writer  reported 
that  the  responsibility  for  the  damage  rested  with 
the  bleacher.  This  was  disputed,  and  a  visit  was 
paid  to  the  bleach  works  to  see  the  cloth  in  bulk. 
The  manager  at  the  works  denied  responsibility. 
He  stated  that  the  pink  colour  could  not  be  discharged 
without  destroying  the  colour  of  the  headings.  He 
had  tried  "souring,"  and  found  that  he  could  dis- 
charge the  stain,  but  only  at  the  expense  of  the 
headings.  Although  "souring"  in  acid  is  not  the 
proper  method  to  adopt  for  coloured  borders,  still  it 
should  not  have  affected  Turkey  Orange  to  this 
extent  and  this  was  pointed  out  by  the  writer. 
H  e  was  then  taken  to  see  the  cloth,  some  of  which 


576      The  Chemistry  and  Practice  of  Sizing. 


had  been  "  soured."  Here  it  was  found  that  the 
borders  had  stood  the  process,  but  the  "headings" 
had  not  The  latter  had  been  reduced  to  various 
shades  of  yellow  and,  in  some  cases,  the  colour  had 
been  discharged  altogether.  The  cause  of  the 
damage  was  at  once  apparent.  The  manufacturer 
had  used  yarns  of  exactly  the  same  shade  for  both 
the  headings  and  the  borders  but  in  the  former  case 
the  weft  was  dyed  with  orange  chrome,  whilst  in  the 
latter,  the  warp  was  dyed  with  Turkey  orange.  In 
the  sample  of  cloth  submitted  to  the  writer  for  exam- 
ination the  ''heading"  was  not  present.  Con- 
sequently, until  the  visit  to  the  bleach  works,  he  was 
ignorant  of  the  fact  that  two  distinct  colours  had  been 
used.  As  a  matter  of  fact  it  had  never  entered  the 
manufacturers  mind  that  this  could  affect  the  results 
obtained  after  bleaching,  and  so  long  as  he  had  used 
yarns  identical  in  shade  of  colour,  he  thought  he  was 
perfectly  safe.  Chrome  orange  is  not  a  suitable 
colour  for  borders  for  goods  which  havetobe  bleached, 
especially  if  a  good  white  be  required.  At  the 
same  time,  if  this  colour  had  been  present  in  the 
cloth  only,  a  careful  bleacher  would  have  preserved 
it.  Even  when  it  was  used  in  conjunction 
with  Turkey  orange,  a  colour  which  always 
"runs"  more  or  less  during  bleaching,  it  might 
have  been  kept  right  if  the  bleacher  had  used 
hyposulphite  of  soda  for  "clearing"  the  "chemic" 
instead  of  giving  it  the  final  "souring"  in  acid, 


Bleaching — "  Coloured  Borders!'  577 


At  the  same  time  such  a  mixture  of  colours 
causes  complications,  and  the  bleacher  can  hardly 
be  held  responsible  for  damage  caused  under  such 
circumstances, 

It  is  not  generally  known  among  bleachers 
that  the  discharged  colours  of  orange  chrome 
can  be  restored  if  treated  quickly.  If  the  damaged 
cloth  had  been  run  through  boiling  milk  of  lime 
in  the  limeing  machine,  after  being  "soured"  with 
the  acid,  the  colours  of  the  headings  would  have  been 
restored,  whilst  the  stain  on  the  body  of  the  cloth 
from  the  Turkey  orange  would  have  been  removed 
by  the  "souring"  process. 

A  knowledge  of  the  chemistry  of  the  chrome  dyes 
will  explain  this. 

(1)  Yellow    chrome    is    a    chromate    of  lead 

(PbCr04). 

(2)  Orange  chrome  is  an  oxychromate  of  lead 

(Pb2OCr04),  and  is  produced  by  boiling 
chromate  of  lead  with  milk  of  lime. 
Both  these  colours  are  destroyed  by  acids;  even 
the  weakest  organic  acids  having  this  effect  on 
the  orange  chrome.  The  changes  which  take 
place  in  converting  the  yellow  chromate  into 
orange  oxychromate  are  shown  by  the  following 
equations : — 

2PbCr04  +  CaH202   =  Pb2OCr04  +  CaCr04  +  H20. 

Yellow  Chromate    Slaked      Orange  Oxychromate    Chromate  Water, 
of  Lead.  Lime.  of  Lead.  of  Calcium. 

K2 


578      The  Chemistry  and  Practice  of  Sizing, 

The  action  of  dilute  hydrochloric  and  other  acids 
on  these  chromes  is  shown  by  the  two  following 
equations : — 

PB2OCr04    +    2HC1    =   PbCU    +    PbCrO^    +  H20. 

Orange  Chrome.    Hydrochloric    Chloride  of   Yellow  Chrome.  Water. 
Acid.  Lead. 

PbCr04     +     2HC1    =    PbCl2     +  H3Cr04. 

Yellow  Chrome.        Hydro-     Chloride  of  lead.  Chromic 
chloric  Acid.  Acid. 

First  the  orange  chrome  is  reduced  to  the  yellow 
chrome,  and  then,  by  further  action  of  the  acid,  it  is 
converted  into  the  colourless  chloride  of  lead. 

It  is  doubtful  however,  whether  this  method  of 
restoring  damaged  colours  is  of  any  practical  value. 
It  is  interesting  from  a  chemical  point  of  view 
only.  The  difficulty  lies  in  the  removal  of  the 
lime  left  in  the  cloth  after  washing.  This  could  only 
be  done  by  "souring,"  and  would,  of  course,  be 
as  fatal  as  it  was  in  the  first  instance. 

It  has  already  been  mentioned  that  some 
bleachers  only  wash  the  cloth  after  "  chemicking," 
instead  of  using  an  "antichlor"  as  well.  This  is 
not  a  good  method,  as  there  is  always  a  danger  of 
leaving  "chemic"  in  the  fabric.  This  would  injure 
the  colours  of  the  borders  and  headings,  and  by 
causing  them  to  "run,"  produce  stains  on  the  cloth, 
especially  on  that  portion  which  has  been  at  the 
bottom  of  the  pile.  Such  a  case  is  here  described. 
The  cloth  wTas  a  dhootie,  woven  with  a  Turkey 
orange  border.    On  examination  it  was  found  to 


Bleaching — Faults  in  Grey  Cloth, 


579 


have  a  pink  stain  in  different  parts  of  the  fabric,  A 
more  careful  examination  disclosed  the  fact  that 
wherever  the  stain  occurred  the  cloth  had  a  harsh 
feel,  as  though  some  mineral  substance  had  dried  on 
it,  and  when  these  places  were  treated  with  dilute 
hydrochloric  acid  the  colour  was  immediately 
discharged,  and,  at  the  same  time  the  smell  of 
"chemic"  (hypochlorus  acid)  was  given  off.  It  was 
at  once  apparent  that  the  cloth  had  not  only  not  been 
treated  with  an  "antichlor,"  but  it  was  also  evident 
that  the  washing  was  superficial  as  there  was  enough 
carbonate  of  lime  present  to  cause  an  effervescence 
when  the  acid  was  added.  The  result  was  that  the 
colour  which  had  bled  remained  on  the  fabric.  The 
bleacher  was  undoubtedly  responsible  for  this  fault. 

Cotton  cloth  is  frequently  damaged  during  the 
processes  of  bleaching  and  the  bleacher  is  not  always 
to  blame.  Very  often  the  trouble  is  due  to  care- 
lessness on  the  part  of  the  spinner  or  the  manu- 
facturer, or  to  the  use  of  certain  ingredients  by  the 
manufacturer  in  the  size.  The  chief  sources  of 
damage  which  occur  through  faults  in  manufacture 
are  generally  due  to  the  presence  of : — 

(1)  Mineral  oil  stains. 

(2)  Paraffin  wax  stains. 

(3)  The  chlorides  of  magnesium,  calcium,  and  zinc, 

in  the  size.  (The  most  objectionable  of 
thesesubstances  is  chloride  of  magnesium,) 

(4)  Oxalic  acid. 


580       The  Chemistry  and  Practice  of  Sizing. 

OIL  STAINS. — These  stains  are  caused  by 
mineral  oil  coming  in  contact  with  the  cloth  or  yarn 
during  the  spinning  or  weaving  operations.  The 
stains  are  not  always  apparent  when  the  cloth  is  first 
bleached,  but  they  generally  show  up  on  dyeing 
or  printing. 

The  effect  of  mineral  oil  is  to  produce  a  pale 
yellow  stain  which  resists  the  dyes,  unless  the  oil 
be  removed  previous  to  bleaching.  In  spinning 
and  weaving  high-class  yarns  which  are  afterwards 
going  to  be  subjected  to  bleaching,  mineral  oil  should 
not  be  used  for  lubricating  the  machinery.  Sperm  oil 
is  the  correct  oil  to  use,  or  at  the  very  least  a  mixture 
of  half  sperm  and  half  mineral  oil.  Oil  dealers 
frequently  offer  mineral  oil  as  "stainless."  There  is 
no  such  thing  as  a  stainless  mineral  oil 'if  it  be  left 
on  the  cloth  and  it  gets  treated  with  "chemic." 
Sometimes  mineral  oil  stains  are  caused  by  the  use  of 
tallow  which  has  been  adulterated  with  mineral  oil. 

Paraffin  Wax  Stains. — These  stains,  like  those 
from  mineral  oil,  are  not  always  apparent  in  the 
bleached  cloth,  but  they  quickly  show  up  on  dyeing 
or  printing  the  fabric.  They  may  be  caused  by  the 
manufacturer  knowingly  using  paraffin  wax  in  his 
size,  or,  as  is  frequently  the  case,  by  his  using  a 
tallow  adulterated  with  mineral  oil  and  paraffin 
wax.  Too  much  care  cannot  be  exercised  in  the 
choice  of  tallow  for  goods  which  have  to  be  bleached 
and  dyed. 


Bleaching — Faults  in  Grey  Cloth.  581 


Cases  are  known  where  manufacturers  have 
used  paraffin  wax  for  years  and  never  had  a  com- 
plaint of  damage.  A  great  deal  depends  upon 
the  treatment  of  the  cloth  in  the  kiers.  In  some 
bleach  works  it  is  customary  to  run  off  the  liquor 
from  the  bottom  of  the  kier,  whilst  in  others  it  is 
customary  to  force  the  liquor  upwards  so  as  to  over- 
flow at  the  top.  It  will  be  readily  seen  that  if  the 
former  procedure  be  adopted  there  is  the  risk  that 
the  paraffin  wax,  which  has  melted  from  the  cloth 
and  floated  on  the  surface  of  the  liquor,  will  be  ab- 
sorbed by  the  top  layers  of  the  cloth  as  the  liquor 
is  run  off,  whereas  by  the  latter  method  of  emptying 
the  kiers,  the  paraffin  wax  will  be  the  first  substance 
to  be  washed  away.  In  one  case  the  wax  is 
removed,  whilst  in  the  other  the  whole  of  the  wax 
from  about  two  tons  of  cloth  may  be  deposited  over 
a  portion  of  the  cloth  only,  and  so  cause  stains. 

Paraffin  wax  stains  are  also  caused  by  the  weavers 
rubbing  the  yarn  with  this  wax  with  a  view  to 
reducing  the  friction  on  the  healds  and  reeds  and 
so  improve  the  weaving.  This  is  a  practice  which 
should  be  stopped  at  once. 

If  the  cloth  has  become  stained  with  mineral 
oil,  it  should  be  removed  by  treating  it  with  benzene 
before  it  is  sent  to  be  bleached,  as  described  on 
page  542. 

Chloride  of  Magnesium. — Chloride  of  mag- 
nesium should  never  be  used  in  the  size  employed 


582      The  Chemistry  and  Practice  of  Sizing. 


for  goods  which  are  intended  for  bleaching.  This 
substance  has  been  the  cause  of  a  great  amount  of 
damage  at  one  time  or  another.  The  injury  is 
caused  to  the  fabric  during  the  singeing  process. 
The  high  temperature  to  which  the  cloth  is  subjected 
decomposes  the  chloride  of  magnesium  with  the 
formation  of  hydrochloric  acid.  This  acid  tenders 
the  fibre,  according  to  the  severity  of  the  singeing 
process  and  to  the  amount  of  chloride  of  magnesium 
present.  In  strong  cloth  the  damage  may  not  be 
apparent  until  the  goods  are  dyed  or  printed.  Then 
it  takes  the  form  of  stains,  on  account  of  the  dye 
being  absorbed  unevenly. 

Many  manufacturers  knowingly  use  chloride  of 
magnesium  in  the  size,  but  there  are  many  cases 
where  it  is  used  unknowingly.  In  the  latter  case  its 
presence  is  due  to  the  use  of  some  secret  prepara- 
tion containing  chloride  of  magnesium. 

It  has  now  become  a  generally  recognised  rule 
that  the  manufacturer  should  be  made  responsible 
for  any  damage  which  can  be  traced  to  the  use  of 
chloride  of  magnesium  in  goods  which  are  intended 
for  bleaching.  It  is  only  right  and  proper  that  it 
should  be  so,  as  there  is  no  necessity  to  use  such  a 
substance  for  "pure  sized"  goods. 

One  reason  why  chloride  of  magnesium  is  used 
in  the  "size"  for  goods  intended  to  be  bleached  is 
because  the  manufacturer  is  asked  by  the  buyer  to 
weight  the  yarn  to  the  extent  of  20  to  30  per 


Bleaching — Faults  in  Grey  Cloth, 


583 


cent.,  and  use  wheaten  flour  instead  of  farina 
or  sago. 

The  reason  given  for  this  is  that  the  cloth 
" finishes"  better  if  it  contains  flour.  This  matter 
has  been  fully  dealt  with  on  pages  301  to  304,  to 
which  reference  should  be  made. 

Chloride  of  Calcium  and  Chloride  of  Zinc: — 
These  are  objectionable  substances  to  use  in  the 
size  for  goods  intended  for  bleaching,  as  they  are 
liable  to  tender  the  warp  when  the  cloth  is  singed. 

Oxalic  Acid. — This  substance  is  used,  as 
previously  stated,  for  the  purpose  of  removing 
"black  oil"  stains.  It  is  a  dangerous  thing  to  use 
for  cloth  which  has  to  be  bleached,  as  it  tenders  the 
cotton  fibre  to  a  marked  degree.  It  may  also 
produce  stains  when  dyed,  through  the  formation 
of  oxycellulose. 

N.B. — This  chapter  is  an  extract  from  "The  Chemistry  and  Practice  of 
Finishing,"  by  Percy  Bean  and  W.  McCleary. 


584      The  Chemistry  and  Practice  of  Sizing. 
Chapter  XVI. 


The  Ventilation  of 
Humidified  Weaving  Sheds. 


A HUMID  atmosphere  is  absolutely  essential 
for  the  successful  weaving  of  cotton  cloth. 
In  this  respect  Lancashire  is  particularly  well 
situated  and  this  is  owing  to  its  geographical 
position.  The  county  has  an  extensive  coast  line 
on  the  west  and  it  is  protected  by  the  long  range  of 
hills  of  the  Pennine  range  on  the  east. 

All  winds,  except  those  from  an  easterly  direc- 
tion, are  more  or  less  moist,  especially  those  from 
the  west  and  south-west,  and  this  moisture  is 
localised  to  a  great  extent  to  Lancashire  by  the 
Pennine  range. 

A  glance  at  a  physical  map  of  England  showing 
the  rainfall  will  explain  one  reason  why  Lancashire 
is  supreme  so  far  as  the  cotton  trade  is  concerned. 
Even  Yorkshire,  on  the  east  of  the  Pennines,  is  very 
much  drier  and  has  a  very  much  less  rainfall  than 
East  and  North-East  Lancashire.  It  is  also  notice- 
able that  those  districts  in  Lancashire  nearest  the 


Relative  Humidity  of  the  Air. 


585 


coast,  especially  in  the  south-west,  and  which  are 
farthest  from  the  hills,  are  much  drier  than  the 
eastern  portions.  For  these  reasons  the  weaving 
districts  are  found  chiefly  in  the  valleys  sheltered  by 
the  Pennine  range. 

Another  advantage  possessed  by  Lancashire  over 
every  other  cotton  centre  in  the  world  is  the  small 
range  of  variation  in  the  temperature  between 
winter  and  summer.  As  will  be  seen  from  the 
following  table  the  average  temperature  in  winter  is 
about  40°  Fah.,  and  the  average  in  the  summer  is 
about  6o°  Fah. ;  the  average  temperature  through- 
out the  year  being  about  47°  Fah. 

Mean   Monthly  Temperature  of   the   Outside  Air  at 


Blackburn  at  9  a.m.  and  9  p.m. — Degrees  Fahrenheit. 


Month. 

1900 

1901 

1902 

1903 

1904 

1905 

T906 

January  

37*9 

36'5 

37'9 

37'5 

37  8 

37*3 

39'3 

33*8 

337 

32*5 

41*5 

35*3 

38-5 

34*5 

March   

365 

37*4 

40-5 

42*1 

37*2 

42-5 

38-8 

April  

45'°5 

45*9 

44-1 

42*2 

45*2 

427 

44-1 

May   

45*6 

S3*i 

45'6 

50-8 

49*2 

5°*3 

48-9 

June  

5^9 

587 

55'8 

52"4 

547 

55*6 

53*4 

July   

61-3 

637 

55^9 

56'9 

60*03 

6o*3 

58-4 

August  .  

57'i 

59*i 

55*5 

55'2 

566 

56*6 

59'5 

55*5 

55*9 

53*9 

54*5 

54*3 

52*9 

56-5 

October  

47'5 

47*5 

47'9 

48-1 

487 

47*4 

49'8 

November  ... 

45'8 

40*06 

43'i 

42*1 

41-4 

39'6 

438 

December  

43*° 

36'4 

387 

36-5 

37'i 

40*3 

35*9 

The  hottest  months  are  July  and  August,  and 
the  coldest  January  and   February,    Even  in  the 


586 


The  Chemistry  and  Practice  of  Sizing. 


coldest  months  the  temperature  rarely  falls  below 
freezing  point,  and  in  the  hottest  months  it  rarely 
exceeds  70°  Fah.  If  these  temperatures  are  com- 
pared with  those  of  other  cotton  centres  there  will 
be  found  a  marked  difference.  In  and  around 
Boston,  U.S.A.,  which  may  be  considered  the 
Lancashire  of  the  United  States,  there  are  extreme 
variations  in  temperature.  The  winter  months  are 
very  cold  and  the  summer  months  very  hot. 
Extremes  of  temperature  play  an  important  part  in 
the  success  or  otherwise  of  the  manufacture  of  cotton 
goods  for  the  following  reason : — 

It  has  already  been  stated  that  a  humid  atmos- 
phere is  absolutely  essential  for  the  manufacture  of 
cotton  cloth  because  moisture  is  essential  to  the 
manipulation  of  cotton  yarn.  Cotton  contains  a  certain 
amount  of  natural  moisture  and  whilst  any  addition 
to  this  moisture  increases  its  strength  and  pliability 
slightly,  a  reduction  reduces  the  strength  and  pliability 
very  greatly  as  the  following  table  will  show: — 

Tests  of  Strength  of  Unsized  Cotton  Yarn. 


Counts  347's. 


Percentage  of 
Moisture. 

Breaking 
Strain  in 
ounces. 

Length  of 
Stretch  in 
inches. 

Loss  of 
Strength. 

Loss  of 
Stretch. 

6*48 

6'43S 

1-087 

4*41 

5-000 

0-772 

22*3  per  cent. 

28*8  percent. 

2'39 

4'77S 

o-68i 

25 8   »  » 

37*4  n  » 

o'4S 

4-780 

0*650 

257    »  » 

4°"2  „  „ 

Dry 

4*215 

0-625 

34*5   >>     »  , 

42'5    »  If 

Humidity — Effect  of  on  Cotton.  587 


Tests  of  Strength  of  Yarn  " Sized" 
with  1 6*5  per  cent,  of  Size.     Counts  36s. 


Percentage  of 
Moisture. 

Breaking 
Strength  in 
ounces. 

Length  of 
Stretch  in 
inches. 

Loss  of 
Strength. 

Loss  of 
Stretch. 

io-iS 

7-223 

0-65 

8'02 

0569 

9*4  per  cent. 

12*6  percent. 

5'94 

5*923 

0*462 

180   „  „ 

28-8  „  „ 

3'94 

5*985 

0*412 

17*2    „  „ 

36*6  11  11 

2"02 

6  090 

0*369 

i5*8   11  11 

43'1  n  11 

Dry 

477 

0*288 

34*o 

55  7  ?i  11 

If  cotton  yarns  be  exposed  to  a  dry  atmosphere 
in  the  process  of  weaving,  the  air  robs  the  cotton  of 
its  natural  moisture  with  the  result  that  weaving  is 
difficult  on  account  of  the  breakages  which  take 
place. 

Although  Lancashire  possesses  a  climate  which  is 
even  more  humid  than  the  average  humidified  shed 
as  shown  by  the  following  table,  and  although  the  tem- 
perature shows  only  relatively  small  variations,  this 
temperature  is  not  high  enough  to  enable  work  to  be 
carried  on  during  a  great  portion  of  the  year  without 
heating  the  air  of  the  weaving  shed.  The  effect 
of  raising  the  temperature  of  air  containing  a  definite 
amount  of  water  is  to  dry  the  air,  although  the 
amount  of  water  contained  in  it  remains  the  same. 
Although  it  is  necessary  to  warm  the  air  of  the 
weaving  shed  in  Lancashire  at  certain  times,  it  is 
not  necessary  to  warm  it  to  the  same  extent  as  it  is 
in  other  countries.    This  is  the  explanation  of  the 


588      The  Chemistry  and  Practice  of  Sizing, 

statement  that  "the  small  range  of  variation  in  the 
temperature  found  in  Lancashire  plays  an  important 
part  in  the  success  of  weaving."  At  no  time  of  the 
year  is  it  necessary  to  raise  the  temperature  of  the 
outside  air  many  degrees  in  order  to  make  it 
comfortable  for  working. 

A  great  many  people  are  not  yet  clear  upon  this 
question  of  relative  humidity  and  its  effect  on  the 
weaving  of  cotton  cloth,  and  very  few  people  are 
aware  that  a  damp  or  humid  atmosphere  may  be 
made  into  a  dry  one  by  heating  it.  In  order  to 
make  this  matter  clearer  the  following  table  should 
be  carefully  examined  : — 

Table  Showing  Effect  of  Heating  a 


Saturated  Atmosphere  from  330  F.  to  70°  F. 


Temperature. 

Relative 
Humidity, 

Grains  of 
moisture 
per  cubic 
foot. 

Grains  of 
moisture  per 
cubic  foot 
required  to  raise 
the  relative 
humidity  to 
82  per  cent. 

Outside  air   

33°  F. 

IOO  per  cent. 

2*2 

Same  air  heated  to 

33  „ 

83  ,1 

2*2 

Do. 

44  ,i 

65  M 

2'2 

0'6  grains 

Do. 

49  » 

55  11 

2*2 

I'l  11 

Do. 

54  » 

47  n 

2*2 

1*7  ,1 

Do. 

60  „ 

37  11 

2*2 

2*5  1, 

Do. 

65  If 

32  »> 

2'2 

3*4  11 

Do. 

70  11 

27  11 

2*2 

4*4  11 

As  a  further  illustration  take  as  an  instance  a 
weaving  shed,  50  yards  square  and  5  yards  high. 


Humidity  of  Air  of  Weaving  Shed.  589 


The  air  of  such  a  shed,  saturated  with  moisture, 
with  a  temperature  at  32  degrees  Fah.,  would  con- 
tain the  vapour  of  1  \  \  gallons  of  water,  and  would,  of 
course,  feel  very  damp.  If  the  temperature  of  the  air 
be  raised  to  65  degrees  Fah.,  and  no  further  moisture 
added,  the  atmosphere  would  then  feel  excessively 
dry.  From  what  has  already  been  said  it  will  be 
realised  that  the  apparent  dryness  or  dampness  of  an 
atmosphere  depends  not  only  on  the  absolute  amount 
of  water  vapour  present,  but  upon  the  temperature 
also.  In  the  example  above,  a  saturated  atmosphere 
at  65  degrees  Fah.  would  hold  the  vapour  of  33 
gallons  of  water,  as  against  1  \\  gallons  at  32 
degrees  Fah. 

It  is  therefore  evident  that  a  cold  atmosphere  may 
be  more  humid  or  moist,  with  very  little  actual 
moisture,  than  a  warm  atmosphere  which  may 
contain  a  very  much  greater  quantity  of  moisture. 
In  other  words,  the  humidity,  or  moistness,  of  an 
atmosphere  depends  not  upon  the  absolute  weight 
of  water  vapour  in  it  but  upon  the  degree  of 
saturation,  Therefore,  if  cold  air  be  admitted  to 
a  weaving  shed,  the  temperature  of  which  is  65 
degrees  Fah.,  and  if  this  air  be  not  humidified, 
the  following  conditions  would  be  produced  : — 

The  cold  air,  whatever  its  condition  of  humidity, 
would  rise  in  temperature,  and  would  then  be  capable 
of  absorbing  a  much  greater  quantity  of  moisture 
than  before.    This  would  have  the  effect  of  drying 


590 


The  Chemistry  and  Practice  of  Sizing. 


the  air  in  the  shed,  although  it  would  still  contain  the 
same  actual  weight  of  moisture.  The  dry  air 
would  then  begin  to  absorb  moisture  from  the 
yarn,  and  from  the  bodies  of  the  operatives. 
Putting  aside  the  question  of  the  operatives, 
this  would  have  disastrous  effects  on  the  weaving. 

It  will  be  seen  that  in  spite  of  the  natural  con- 
ditions possessed  by  Lancashire,  there  are  many  days 
when  it  is  necessary  to  introduce  moisture  into  the 
sheds,  to  compensate  for  the  loss  of  humidity  brought 
about  by  warming  the  air,  in  order  to  obtain 
good  weaving.  During  cold  weather  and  dry 
east  winds  weaving  is  difficult  for  reasons  already 
given,  even  where  the  strongest  yarn  only  is 
used. 

The  following  table  further  illustrates  the  change 
which  takes  place  when  a  change  in  temperature  is 
made.  In  the  first  column  a  number  of  temperatures 
are  given,  starting  at  30°  Fah,,  and  going  up  to 
70°  Fah.  At  each  temperature  the  air  issaturated  with 
moisture.  When  the  temperature  is  raised  the  per- 
centage of  saturation  is  lowered,  because  at  the  higher 
temperature  the  air  is  capable  of  taking  up  a  great 
deal  more  moisture.  In  other  words  the  air  is 
rendered  drier  as  the  temperature  increases.  Thus 
if  it  be  saturated  at  30°  Fah.,  i.e.,  contains  100 
per  cent,  relative  humidity,  and  it  is  raised  to 
8o°  Fah.  without  the  addition  of  more  moisture, 
it   would    contain    only    18*2    per    cent,  relative 


Humidity  of  Outside  Air. 


591 


humidity  and  in  this  condition  it  would  be 
irritatingly  dry. 

Humidity 

of  air  Humidity  of  the  air 

Saturated  at        Raised  in  temperature  to — 

Degree.  Per  Degree.  Per  Degree.   Per  Degree.   Per  Degree.  Per  Degree.  Per 
cent.  cent.  cent.  cent.  cent.  cent. 

30=100  40=69    50=48*8    60=34*5    70=25  80=18*2 

40=100  50=  70*7    60=50      70=36*380  =  26*4 

50=100  60  =  707    70=  51-3  80=37.3 

60=100  70  =  72*580  =  527 

70=100  80=72*7 

Another  illustration,  showing  the  converse  con- 
ditions, is  the  production  of  November  fogs.  Nov- 
ember is  generally  a  moderately  warm  month  in  the 
day  time,  with  a  fair  amount  of  bright  sunshine. 
It  is  also  a  month  wherein  the  atmosphere  is  nearly 
at  the  point  of  saturation  as  regards  moisture.  Whilst 
the  days  are  warm,  the  nights  are  usually  cold.  It 
will  be  noticeable  that  if  there  is  a  particularly  bright 
day  followed  by  a  frosty  night,  dense  fog  occurs  next 
day.  This  is  brought  about  through  lowering  the 
temperature  of  a  nearly  saturated  atmosphere,  and  so 
making  it  that  at  the  lower  temperature  it  cannot  hold 
in  solution  the  moisture  previously  contained  in  it. 

Whilst  dealing  with  this  question  of  humidity  it 
may  be  as  well  to  explain  clearly  why  east  winds  and 
cold  frosty  days  make  weaving  bad. 

East  winds  are  generally  set  down  as  cold, 
whereas  as  a  matter  of  fact  they  may  be  no  colder 
than  west  winds.  What  is  really  the  case  is  that 
they  are  dry  and  cause  a  sensation  of  coldness  on 


592       The  Chemistry  and  P  7' act  ice  of  Sizing. 

account  of  robbing  the  surface  of  the  body  of  moisture. 
The  rapid  evaporation  of  moisture  cools  the  surface 
of  the  body  and  produces  a  feeling  of  coldness.  The 
same  thing  occurs  when  the  dry  air  is  sent  into  the 
weaving  shed.  It  absorbs  moisture  as  soon  as  it  enters 
the  shed  and  so  robs  the  cotton  of  its  natural  moisture. 

Similar  conditions  arise  in  cold  frosty  weather. 
As  soon  as  the  air  enters  the  weaving  shed  it  becomes 
warmer  and  then  robs  the  fibre  of  its  moisture. 

Comparisons    between    the    temperature  and 
relative  humidity  of  three  humidified  sheds,  at  that 
time  under  the  management  of  Mr.  F.  Scarisbrick, 
and  the  outdoor  air  of  Blackburn  are  shown  for  the 


year  1906. 


1906. 

The  Three 

Humidified 

Outside 

Air  at 

Sheds. 

Black 

burn. 

Month. 

Average 
Temperature. 

Relative 
Humidity. 

Average 
Temperature 
at  9  a.m. 

Relative 
Humidity. 

59'2°F. 

79-9% 

39'3° 

F. 

93'4% 

56-9°  F. 

8o-o% 

34"5° 

F. 

88-4% 

March  

S9'5°  F. 

79-7% 

38-8° 

F. 

85-8% 

April   . .  

627°  F. 

78-6% 

44-1° 

F. 

72-5% 

May  

66-5°  F. 

79-4% 

48-9° 

F. 

83-3% 

June   

73-1°  F. 

76-2% 

53-4° 

F. 

78-5% 

July  

73-1°  F. 

76-3% 

58-4° 

F. 

80-3% 

August   

74-2°  F. 

75-4% 

59-5° 

F. 

82-8% 

September   

70-5°  F. 

76-2% 

56-5° 

F. 

79-03% 

October   

66-5°  F. 

777% 

49-8° 

F. 

85-6% 

November   

63-0°  F. 

79-5% 

43-8° 

F. 

90-5% 

December   

58-5°  F. 

79-5% 

35-9° 

F. 

93-09% 

Yearly  Average 

65-3°  F. 

78-2% 

46-9° 

F. 

84-43% 

Relative  Humidity  of  Outside  Air.  593 


The  three  weaving  sheds  gave  an  average  of 
78*2  per  cent.,  whilst  the  average  for  the  outside 
air  of  Blackburn  was  84*43  Per  cent.,  thus  showing 
that  the  outside  air  is  more  humid,  or  damper,  than 
the  inside  of  a  weaving  shed  where  steam  is  intro- 
duced.  It  must  be  clearly  understood  that  by 
humidity  it  is  not  intended  to  mean  rain.  The 
hygrometers  by  which  the  results  are  obtained  are 
protected  from  wet  weather. 

It  may  be  of  interest  to  give  a  detailed  list  of  the 
relative  humidity  of  the  atmosphere  in  Blackburn. 
This  town  is  the  largest  weaving  centre  in  the 
world  where  moisture  is  artificially  introduced  into 
the  weaving  sheds. 


The  "Mean"  Monthly  Relative  Humidity  of  the 
Outside  Air  of  Blackburn. 


Month. 

1900 

1901 

1902 

1903 

1904 

1905 

1906 

January  

95*i 

93'9 

887 

91-1 

94'o 

89-4 

93'4 

February   

95*5 

94-1 

91-9 

897 

9o*3 

88*8 

88-4 

March   

8512 

857 

9**3 

863 

86-i 

86-2 

85-8 

April  

83-6 

76-6 

813 

79*4 

Sr6 

832 

725 

May   

76-9 

72-9 

8r7 

77-6 

76-6 

78-2 

83-3 

June   

79-0 

73*6 

62*4 

72  9 

76*1 

75  3 

78-5 

My   

77-5 

77-2 

8ro8 

821 

77*3 

767 

80  3 

August   

82*8 

78-3 

85-0 

87-9 

8i'3 

792 

82-8 

September  ... 

85-0 

79-6 

82-9 

83-2 

79-6 

847 

79'°3 

October   

90-3 

87-1 

920 

85-6 

863 

83-0 

85-6 

November  ... 

9°'5 

8o-8 

85-08 

91*2 

9I-3 

90*1 

9°'5 

December  

894 

918 

89-5 

90  9 

91  5 

91-1 

93°9 

Yearly  Average 

8S-9 

826 

84*4 

84'8 

84*3 

83'8 

84-4 

L2 


594      The  Chemistry  and  Practice  of  Sizing. 

Whilst  dealing  with  the  question  of  relative 
humidity  it  might  be  as  well  to  show  by  some 
comparison  what  is  meant  by  the  terms  "damp" 
and  "dry." 

Air  containing  90%  to  100%  relative  humidity  is  very  damp. 
„         »        80  „  „    90  „      „  „       „  damp. 

„         „        70  „  „    80  „  „  neither  damp  nor  dry. 

„         »        60 »  »    7°  »      »  »        is  dry. 

»         n        5°  »  5,    60  „      „  „        „  very  dry. 

„         „        less  than  50%  is  uncomfortably  dry. 

The  average  relative  humidity  throughout  the 
British  Isles  is  about  80%. 

From  these  explanations  it  must  be  apparent 
that  in  order  to  carry  on  the  business  of  cotton 
manufacturing  the  air  of  the  weaving  shed  must 
be  "conditioned"  in  order  to  keep  it  at  a  regular 
temperature  and  in  a  regular  state  of  humidity. 

Without  desiring  to  enter  into  the  controversal 
side  of  the  question  of  "steaming"  the  authors  firmly 
believe  that  a  weaving  shed  where  "steaming""  is 
carried  on,  and  which  is  suitably  ventilated,  is  a  far 
healthier  workshop  than  any  of  the  so-called  "dry 
sheds"  which  are  not  humidified  and  which  are  not 
ventilated  by  power.  This  opinion  is  strongly 
supported  in  the  report  published  by  the  Chief 
Inspector  for  Factories  in  1905.  It  is  not  suggested 
that  "steaming"  is  a  direct  benefit  to  health  by  any 
means.  The  opinion  is  based  upon  the  vastly 
improved  conditions  obtained  through  the  ventilation 
of  such  workshops.     These  conditions  do  not,  and 


Effect  of  High  "  Wet  Bulb  "  Temperatures.  595 


cannot  exist  in  non-steaming  places  if  weaving  has 
to  be  carried  on  at  all. 

A  moderate  percentage  of  moisture  at  moderate 
temperatures  in  well  ventilated  sheds  is  far  less 
harmful  than  the  presence  of  "air  sewage"  in  a  "dry" 
but  badly  ventilated  shed.  It  is  only  when  the 
wet  bulb  temperature  is  high  that  unhealthy  and 
disagreeable  conditions  arise. 

The  operatives  have  more  to  gain  in  health  and 
comfort  by  insisting  upon  a  good  atmosphere  to  work 
in,  i.e.,  one  in  which  the  amount  of  organic  matter 
is  low,  than  by  agitating  for  the  total  abolition  of 
"steaming."  They  would  have  had  reasonable 
grounds  for  complaint  had  not  the  question  of 
ventilation  been  raised,  and  the  conditions  of  the 
atmosphere  greatly  improved, 

In  order  to  protect  the  weaver  against  humid 
conditions  at  high  temperatures  a  schedule  was 
drawn  up  and  incorporated  in  the  Cotton  Cloth 
Factories  Act.  If  the  temperatures  and  limits  of 
humidity  are  examined  in  this  table  (shown  on 
page  601),  it  will  be  noticed  that  as  the  temperature 
rises  there  is  a  decrease  in  the  percentage  of 
humidity  allowed.  Since  this  table  was  arranged 
by  the  authorities  it  has  been  found  out  that  the 
depressing  effects  produced  by  working  in  a  warm 
moist  atmosphere  are  more  accurately  determined 
by  the  temperature  of  the  "wet  bulb"  thermometer 
than  by  the  percentage  of  humidity. 


596      The  Chemistry  and  Practice  of  Sizing. 


Instead  of  any  alteration  taking  the  form  of 
lowering  the  percentage  of  humidity  at  high  tem- 
peratures there  is  every  probability  that  a  maximum 
"wet  bulb"  temperature  will  be  fixed  for  cotton  cloth 
factories.  The  depressing  effects  of  high  "  wet  bulb" 
temperatures,  and  the  accompanying  rise  of  body 
temperatures,  are  most  marked  in  persons  who  are 
not  acclimatised  to  these  conditions.  Those  who 
are  accustomed  to  working  under  certain  conditions 
become  '"seasoned"  to  them,  whereas  strangers  to  a 
warm  moist  atmosphere  will  suffer  much  greater 
discomfort,  and  this  must  be  taken  into  consideration 
by  those  who  investigate  these  matters. 

At  the  same  time  there  is  no  doubt  that  an 
atmosphere  having  a  high  "wet  bulb"  temperature 
produces  bodily  discomfort.  The  temperatures  at 
which  this  feeling  of  discomfort  begins  depends  to  a 
certain  extent  upon  the  amount  of  air  movement 
which  accompanies  the  "wet  bulb"  temperature. 
A  higher  temperature  can  be  borne  where  there 
is  plenty  of  ventilation  than  where  the  air  is 
stagnant. 

As  previously  stated  people  accustomed  to  certain 
conditions  become  acclimatised  to  them,  and  there 
will  be  less  rise  in  body  temperature  with  those 
people  than  with  people  who  are  strangers  to  the 
conditions.  It  is  not  possible  to  say  what  are  the 
physiological  effects  of  working  in  an  atmosphere 
which  produces  a  rise  of  body  temperature.  One 


Effect  of  High  "  Wet  Bulb  "  Temperatures.  597 

thing  is  certain  and  that  is,  the  effects  cannot  be 
beneficial. 

With  a  view  to  obtaining  some  practical 
information  on  the  effects  of  working  in  an  atmos- 
phere  having  a  high  "wet  bulb"  temperature  a  series 
of  experiments  were  undertaken  by  Mr.  Fred 
Scarisbrick,  under  the  guidance  and  control  of 
Dr.  Howarth,  Medical  Officer  of  Health  for 
Darwen. 

These  experiments,  the  results  of  which  are 
given  in  the  following  tables,  consisted  of  climbing 
a  ladder,  three  feet  high,  a  certain  number  of  times 
a  minute.  At  intervals  of  ten  minutes  the  mouth 
temperature  was  taken,  and  the  results,  with  any 
observations,  were  noted  by  Dr.  Howarth.  The 
experiments  were  conducted  in  a  room  specially 
arranged  for  the  purpose.  The  temperature  and 
the  degree  of  humidity  were  under  control,  but  there 
was  no  system  of  ventilation  installed,  and  this  was 
the  only  difference  between  the  room  and  a  humidi- 
fied weaving  shed. 

In  order  to  compare  the  effects  produced  on 
Mr.  Scarisbrick  with  the  effects  on  the  weavers 
in  the  shed,  who  were  working  in  similar  temperatures 
(this  day  was  the  hottest  day  of  the  year),  the  "mouth 
temperatures"  of  a  number  of  weavers  were  taken. 
These  are  shown  in  the  table  on  page  600.  It  is 
noteworthy  that  the  " mouth  temperatures"  of  the 
operatives  were  lower,  at  the  same  "wet  bulb" 


598       The  Chemistry  and  Practice  of  Sizing, 

temperature,  than  was  shown  by  Mr.  Fred 
Scarisbrick  in  his  three  series  of  experiments. 
This  may  have  been  due  to  the  fact  that  the 
weaving  shed  was  much  better  ventilated  than 
the  room  in  which  the  ladder  climbing  experiments 
were  conducted,  or  it  may  have  been  due  to 
the  operatives  being  more  ''seasoned"  to  a  humid 
atmosphere  and  to  performing  less  work  in  a  given 
time. 

Experiments  made  at  George  Street  Mills. 


A  Ladder,  3  Feet  High,  was  Climbed  Twice 
a  Minute.      March  ioth,  1908. 


Time. 

Temperature 
of  Dry  Bulb. 

Temperature 
of  Wet  Bulb. 

Mouth 
Tem- 

Observations. 

perature. 

3-15 

85'0°F. 

78;o°F. 

98-5 

3-25 

85*0  „ 

79'5  >, 

99-1 

slight  perspiration. 

3-35 

84*8  „ 

79'°  » 

99-2 

profuse  „ 

3-45 

847  » 

79'3  » 

99'3 

5)  55 

3-55 

84'8  „ 

79'6  >i 

99-2 

55  55 

4-5 

1     84'8  „ 

78-5  „ 

99-2 

5  5                      5  5 

4-i5 

83'8  „ 

78-o  „ 

99'3 

5  5                      5  5 

4-25 

34  5 

79'2  » 

99*3 

5'  55 

4-35 

85*0  „ 

79*8 

99*3 

5  5                      5  5 

4-45 

847  V 

797  5> 

99-2 

5  5                      5  5 

4-55 

85-0  „ 

So'o  ,, 

99-2 

5  5                      5  5 

5-5 

86-o  „ 

80  2 

99-2 

5  5                      5  5 

5-i5 

85*5  „ 

79'°  » 

99*4 

turned  on  more  steam 
in  order  to  raise  the 

5-20 

85'5  M 

82*0  j, 

wet  bulb  temperature. 

5-25 

86-o  „ 

83*0  » 

99-6 

turned  off  steam. 

5-3° 

86-o  „ 

76-5  „ 

99*4 

stopped  exercising. 

6-0 

83-0 

75*o  1, 

99-2 

Effect  of  High  "  Wet  Bulb''  Temperatures.  599 

It  will  be  noticed  that  the  "mouth  temperature," 
shown  in  the  experiments  given  on  page  598, 
only  rose  from  98*5°  Fah.  to  99*4°  Fah.  in  the  two 
hours'  work  from  3-15  p.m.  to  5-15  p.m.,  in  an  atmos- 
phere having  a  "  wet  bulb"  temperature  ranging  from 
78°  Fah.  to  80*2°  Fah.,  but  when  the  "wet  bulb" 
temperature  was  increased  at  5-30  p.m.,  the  mouth 
temperature  quickly  rose  to  99*6°  Fah. 


A  Ladder,  3  Feet  High,  was  Climbed  3  times 
a  Minute.      March  17TH,  1908. 


Time. 

Temperature 
of  Dry  Bulb, 

Temperature 
of  Wet  Bulb. 

Mouth 
Tem- 
perature. 

Observations. 

3-20 

87*o°F. 

79*5°F. 

98'6 

3-3° 

36-o  „ 

79'°  » 

99-2 

3-40 

85*0  „ 

78-o  „ 

99'S 

perspiring 

3-5° 

857  „ 

79'o  „ 

99*4 

31 

4-0 

85*2  ,, 

78'5  ,, 

99-6 

33 

4-10 

86-o  „ 

800 

997 

heavy  perspiration 

4  20 

86-o  „ 

79'2  >s 

99^ 

)>  n 

4-3° 

85*8  „ 

78-8  „ 

99*6 

33  33 

4-40 

85-6  „ 

78-2  „ 

997 

33  33 

4-5° 

86-o  „ 

79'2  is 

99*8 

33  3) 

85*8  „ 

79*2  is 

997 

33  33 

5-10 

857  „ 

79'1  ss 

99-8 

33  33 

5-20 

8S'o  » 

777  ,s 

IOO'O 

33  33 

In  this  experiment  there  was  a  rise  of  1*4°  Fah. 
in  the  u mouth  temperature"  after  two  hours'  heavy 
work  in  an  atmosphere  having  a  "wet  bulb"  tem- 
perature ranging  from  78°  Fah.  to  8o°  Fah. 


6oo      The  Chemistry  and  Practice  of  Sizing. 


A  Ladder,  3  Feet  High,  was   Climbed  4  times 
a  Minute.      March  19TH,  1908. 


Time. 

Temperature 
of  Dry  Bulb. 

Tern  perature 
of  Wet  Bulb. 

Mouth  1 
Tem- 
perature, 

Observations. 

4-0 

86'5°F. 

79'5°F. 

98*0 

A- 1  O 

87*0 

7Q'o 

q8'Q 

perspiring. 

4-20 

87-0  „ 

78-0  „ 

99T 

5) 

4-3° 

87-S  » 

79'°  >i 

99*2 

heavy  perspiration 

4-40 

88-o  „ 

8o-o  „ 

99*4 

?>  >» 

4-5° 

88-o  „ 

79'°  m 

99-6 

M 

5-° 

88  0  „ 

79"°  » 

996 

»l  5> 

5-10 

88-o  „ 

8o*o  „ 

99-8 

5>  » 

5-20 

88-2  „ 

79'2  » 

998 

)> 

5-3° 

88-o  „ 

ITS  » 

99-8 

Temperatures  oe  Hygrometers  and  Mouth 
Temperatures  oe  Weavers  in  Townsfield  Shed. 
July  2nd,  1908. 


Time. 

Temp,  of 
Dry  Bulb. 

Temp,  of 
Wet  Bulb. 

Weaver's 
Number. 

Description  of 
Weaver. 

Temp,  of 
Mouth. 

3-45 

88'0°F. 

79'5°F. 

366 

middle  aged  man 

98-6 

4-0 

88-o  „ 

79'5  •> 

394 

young  woman 

98-6 

4-5° 

88*o  „ 

79'5 

444 

girl  13  years 

99  "o 

4-55 

88-o  „ 

79*5  » 

474 

young  woman 

987 

5-o 

88  0  „ 

79'5  „ 

248 

man 

98-4 

5-5 

88-o  „ 

79-5 

324 

young  woman 

98-S 

5-10 

88-5  „ 

79'5  » 

284 

young  man 

99-0 

5-i5 

88  5  „ 

79'5  » 

350 

half-timer  1  2  yrs 

98*6 

All  the  above  worked  in  the  centre  of  the  shed  near  the 
hygrometer  and  were  picked  haphazard. 


Maximum  Limits  of  Humidity. 


60 1 


Maximum  Limits  of  Humidity  of  Atmosphere 
at  given  Temperatures. 


Grains  of  Vapour 
per  Cubic  Foot 
of  Air. 


II. 

Dry  Bulb 
Thermometer 
Readings. 

Degrees  Fahr. 


III. 

AVet  Bulb 
Thermometer 
Headings, 

Degrees  Fahr. 


1  '9 

2'0 
2'1 
2'2 
2'3 

2-4 

2*5 
2'6 

27 

2'8 

2-  9 

31 

3-  2 
3*3 
3 '4 
3*5 

36 

3-  8 
3'9 
4'i 

4-  2 

4*4 
4*5 
47 
4*9 
5'i 
5*2 
5*4 

5-  6 
5'8 

6-  o 

6'2 

6-4 
6-6 

6-  9 
7'i 
7'i 
7i 
7*4 
7 '4 

7-  65 
77 


35 
36 
37 
38 
39 
40 

41 

42 

43 
44 
45 
46 

47 
48 
49 
5o 
5i 
52 
53 
54 
55 
56 
57 
58 
59 
60 
61 
62 

63 
64 

65 

66 

67 


70 
7i 
72 
73 
74 
75 
76 


33 
34 
35 
36 
37 
38 
39 
40 

41 

42 
43 
44 
45 
46 

47 
48 
49 
5o 
5i 
52 
53 
54 
55 
56 
57 
58 
59 
60 
61 
62 

63 
64 

65 

66 

67 

68 

68-5 

69 

70 

70'5 
71-5 
72 


IV. 

Percentage  of 
Humidity. 

Saturation  — 100. 


80 
82 
83 
83 
84 
84 
84 


84 
85 

86 
86 
86 
86 
86 
86 
86 
86 
86 
87 
87 
87 
87 
88 
88 


88 
88 
88 
88 
88 


85'5 

84 

84 

81 '5 

8i'5 

79 


602       The  Chemistry  and  Practice  of  Sizing. 

Maximum  Limits  of  Humidity  of  Atmosphere 
at  given  Temperatures 


(  Continued). 


I. 

Grains  of  Vapour 
per  Cubic  Foot 
of  Air. 

II. 

Dry  Bulb 
Thermometer 
Readings. 

Degrees  Falir. 

in. 

II  Ct   J_>  LI  1 1 J 

Thermometer 
Readings. 

Degrees  Fahr. 

IV. 

Percentage  of 
Humidity. 

Saturation=100. 

8*o 

77 

73 

79 

8-o 

73*5  .» 

77 

8-25  ... 

79 

74'5 

77*5 

8 '55  - 

80 

75*5  - 

77*5 

8*6 

81 

76  ... 

76 

865  ... 

82 

76'5 

74 

8-85  ... 

83  ... 

77'5  - 

74 

8-9  ... 

84 

78 

72 

9-2  .. 

85 

79 

72 

9*5  - 

80 

72 

9*55  ••■ 

..       87  ... 

...       80-5  ... 

71 

9*9 

88 

Svk  ... 

7i 

10*25 

...       89  ... 

...      82*5  ... 

71 

10*3 

90 

...      83  .. 

...  69 

10-35 

91 

83-5  .. 

68 

107  ... 

92 

...      84'5  - 

68 

1 1  -o 

93 

...      85-5  ... 

68 

hi 

94 

86 

66 

n-5  ... 

95 

...       87  ... 

66 

1 1 -8 

...       96  ... 

88 

66 

11-9  ... 

97 

88-5  ... 

-  65-5 

I2*0 

...       98  ... 

...       89  ... 

...  64 

12*3 

99 

90 

...  64 

127 

100 

91 

..  64 

VENTILATION. 

Ventilation  is  the  science  of  removing  vitiated 
air  from  a  building,  and  circulating  fresh  air  with- 
out creating  draughts. 

There  are  two  principles  of  ventilation,  viz. :  the 
natural  or  extraction  principle,  and  the  pressure  or 
plenum  principle.  All  systems  of  ventilation  are 
modifications  and  adaptations  of  these  two  principles. 


The  Ventilation  of  Weaving  Sheds.  603 

EXTRACTION  PRINCIPLE. 

Ventilation  by  extraction  may  be  carried  out  by 
means  of  fans,  or  by  allowing-  the  vitiated  air  to 
escape  through  openings  at  the  ceiling  made  for  the 
purpose.  The  air  thus  removed  is  replaced  by 
air  entering  at  a  lower  level. 

Until  recent  years  all  ventilation  was  carried  out 
on  the  extraction  principle  because  it  was  the 
easiest  to  adapt  to  the  general  run  of  buildings. 

The  extraction  principle  by  means  of  fans  as 
applied  to  weaving  sheds  has  many  advantages  if 
properly  carried  out.  The  fans  are  easily  fixed  and, 
as  there  is  no  heating  apparatus  attached  to  the 
trunks,  there  is  practically  nothing  to  get  out  of  order. 

Unfortunately  the  science  of  mill  ventilation  has 
been  little  understood  in  the  past,  and  in  consequence 
ventilation  by  extraction  fell  into  ill  repute  because 
it  failed  at  the  time  to  bring  weaving  sheds  within 
the  "Act,"  One  idea  seems  to  have  possessed  all 
engaged  in  ventilation,  and  that  was  to  place  the 
extraction  fans  as  high  up  as  possible.  In  a  weaving 
shed  this  is  fatal  to  success,  because  the  only  places 
ventilated  by  this  arrangement  would  be  the  bays  in 
the  roof,  from  the  gulley  to  the  top  of  the  glass. 

By  lowering  the  point  of  extraction  the  air 
which  enters  the  shed  to  replace  that  which  has 
been  removed  is  better  diffused  at  the  breathing" 
height  than  would  be  possible  by  having  the  fans 
high  up. 


604      The  Chemistry  and  Practice  of  Sizing. 

An  instance  of  this  was  shown  in  a  certain 
notable  case  in  which  the  Factory  Inspector  prose- 
cuted under  the  "  ventilation  clause"  of  the  Cotton 
Cloth  Factories  Act.  He  lost  his  case  on  a 
technical  point,  but  the  firm  of  manufacturers  feared 
an  appeal,  and  called  in  the  writer  to  suggest  some 
means  by  wrhich  the  shed  could  be  put  right. 

The  amount  of  air  passing  out  of  the  fan  trunks 
was  measured,  and  it  was  found  that  there  were 
more  fans  being  used  than  were  necessary  to  bring 
the  shed  well  within  the  Act.  The  fans  were  fixed 
to  trunks  which  came  through  the  slates  for  a 
distance  of  about  three  feet.  These  trunks  were 
bent  at  right  angles,  thus  causing  the  fans  to  face 
the  glass  roof.  What  possessed  an  engineer  to 
place  them  in  this  position,  at  this  height,  is 
beyond  the  imagination.  It  is,  or  should  be  a  wrell- 
known  fact  that  a  large  bulk  of  the  air  drawn  in  by 
all  extraction  fans  in  weaving  sheds  comes  through 
the  slates  and  plaster,  and  through  crevices  at  the 
bottom  of  the  glass.  Therefore,  if  the  fans  are 
placed  near  the  roof,  fresh  air  is  drawn  into  the 
shed  and  immediately  extracted  at  the  roof  before 
it  has  reached  the  breathing  height.  The  writer 
saw  at  once  that  the  shed  contained  more  than 
a  sufficient  number  of  fans  to  move  the  required 
volume  of  air  but  .that  it  was  not  being  properly 
distributed.  In  order  to  bring  this  about  he 
arranged  to  have  the  trunks  containing  the  fans 


1 he  Ventilation  of  Weaving  Sheds.  605 

lengthened  so  that  they  reached  to  about  eight  feet 
from  the  floor  level.  The  air  was  afterwards 
analysed  and  found  to  contain  nearly  50  per  cent, 
less  carbon  dioxide  than  before.  Lengthening 
the  trunks  caused  the  air  to  be  circulated  at  a  much 
lower  level  than  before.  Not  only  was  this  most 
important  advantage  secured,  but  the  fans  had  far 
greater  power  to  act  upon  the  air  immediately 
breathed  by  the  operatives,  because  the  points  of 
extraction  were  so  much  nearer  to  the  breathing- 
height.  As  a  matter  of  fact  the  improvement  was 
entirely  due  to  the  fresh  air  beingdiffused  throughout 
the  weaving  shed  instead  of  being  immediately 
removed  before  it  had  any  effect. 

Lengthening  the  trunks,  as  described  above,  is 
not  a  scientific  way  of  overcoming  the  difficulties  of 
extracting  at  a  low  level.  In  the  first  place  there  is 
the  disadvantage  of  having  the  strap  working 
through  a  hole  in  the  trunk.  In  the  second  place  it 
is  difficult  to  adjust  the  strap  when  necessary,  and 
there  is  a  difficulty  in  lubricating  the  various  parts. 
The  fan  is  also  in  an  awkward  position  for  cleaning. 

It  has  often  occurred  to  the  authors  that  if  the 
fans  could  be  arranged  so  as  to  be  driven  at  any 
height  not  exceeding  7  feet  6  inch  to  9  feet  from  the 
floor  one  of  the  greatest  objections  to  ventilation 
by  means  of  extraction  would  be  overcome.  This 
can  be  done  by  using  a  trunk  which  is  bent  at  right 
angles,  so  that  the  fan  works  vertically  instead 


606      The  Chemistry  and  Practice  of  Sizing. 

of  horizontally.  The  Union  Engineering  Co.  of 
Darvven,  have  applied  this  principal  most  success- 
fully. The  fan  constructed  by  this  firm  has  a  spec- 
ially long  spindle  on  the  fan  pulley  to  withstand  the 
strain  of  driving.  When  the  fans  are  fixed  in  the 
way  described  there  is  no  half  twist  in  the  strap,  and 
there  is  no  difficulty,  such  as  is  usually  experienced 
with  extraction  fans,  of  keeping  the  strap  on.  The 
fans  can  be  cleaned  and  lubricated  with  the  minimum 
amount  of  trouble.  An  illustration  of  the  arrange- 
ment  is  shown  on  plate  xix. 

In  spite  of  the  fact  that  the  extraction  principle 
has  many  advantages  when  rightly  applied,  there 
are  a  number  of  objections  to  it.  In  the  first  place 
there  is  no  control  of  the  source  from  which  the  air 
may  come.  It  may  be  drawn  from  closets,  and  other 
objectionable  places,  whereas  under  the  plenum 
principle  the  air  is  forced  into  the  shed  from  definite 
positions.  (In  modern  weaving  sheds  the  above 
objections  do  not  exist  because  closets  arenotattached 
to  the  buildings).  In  the  second  place  extraction  fans 
often  cause  draughts  near  the  doors  or  other  large 
inlets  in  the  shed.  This  is  not  only  objectionable  as 
far  as  the  weaver  is  concerned,  but  it  often  produces 
bad  weaving  places.  This  objection  however,  can 
be  overcome  by  a  little  skill  in  arrangement. 

The  extraction  principle  is  more  suitable  for 
small  sheds  (not.  exceeding  about  300  or  500  looms), 
than  it  is  for  large  sheds.    The  reason  for  this  is 


The  Ventilation  of  Weaving  Sheds,  607 


that  a  large  proportion  of  the  air  comes  through 
the  walls  and  doorways,  and  if  this  air  has  to  travel 
a  considerable  distance  before  it  is  extracted,  it  will 
become  more  contaminated  than  if  it  has  to  travel  a 
shorter  distance. 

Under  the  extraction  system  a  large  weaving 
shed  may  vary  according  to  the  outside  conditions. 
If  the  wind  blows  from  the  east  the  shed  will  be 
found  to  contain  more  carbon  dioxide  on  the  west 
side,  and  vice-versa,  and,  unless  a  large  shed  be  over- 
ventilated  it  is  difficult  to  keep  all  parts  of  it  within 
the  "Act."  The  plenum  system  is,  of  course, 
independent  of  winds,  because  the  pressure  comes 
from  within  and  not  from  without. 

PLENUM  PRINCIPLE. 

At  the  present  time  the  plenum  principle  is  the 
most  popular  amongst  ventilating  engineers,  and 
there  are  many  reasons  for  this. 

In  the  first  place  the  fresh  air  is  forced  into  the 
weaving  shed  from  definite  positions.  This  prevents 
foul  air  from  closets,  fermenting  rooms,  and  other 
objectionable  places,  getting  into  the  shed. 

In  the  second  place  the  air  can  be  filtered,  and 
also  "conditioned,"  before  it  enters  the  shed. 

In  the  third  place  the  air  is  warmed  before  it 
enters  the  shed,  and  there  is  no  danger  of  cold  air 
affecting  either  the  operative  or  the  weaving. 


608      The  Chemistry  and  Practice  of  Sizing. 

Wherever  the  plenum  principle  is  employed  it  is 
essential  that  a  "steaming-1'  or  "conditioning" 
apparatus  should  be  attached  to  it,  otherwise  it  will 
spoil  the  weaving.  In  a  great  many  cases  the 
plenum  system  has  been  adopted  in  sheds  already 
fitted  with  steam  jets.  In  these  cases  there  is  not 
the  same  necessity  to  humidify  the  air  as  it  enters, 
but  it  would  be  better  if  it  were  done. 

The  plenum  principle  is  applied  in  various  ways 
by  ventilating  engineers.  Some  use  centrifugal  fans 
or  " pressure  blowers,"  others  reverse  the  ordinary 
type  of  fan  and  force  air  into  the  shed  instead  of 
extracting  it.  Some  engineers  force  the  air  through 
a  series  of  air  ducts,  either  by  means  of  a  steam  jet 
or  by  means  of  a  " pressure  blower."  A  short 
description  of  the  principal  types  of  ventilating 
systems  may  be  of  interest. 

Amongst  the  principal  firms  who  have 
successfully  dealt  with  the  ventilation  of  weav- 
ing sheds  under  the  plenum  system  may  be 
mentioned,  Matthews  &  Yates  Ltd.,  Swinton; 
James  Howorth  &  Co.  Ltd.,  Farnworth;  the 
Union  Engineering  Co.  Darwen ;  and  Messrs. 
Thomas  Gregson,  Great  Harwood. 

A  simple  form  of  ventilating  apparatus,  on  the 
plenum  principle,  is  made  by  Messrs.  Thomas 
Gregson,  of  Great  Harwood.  This  apparatus 
contains  a  heating  coil  for  warming  the  air,  but  it 
has  no  humidifying  attachment. 


Ventilation  of  Spinning  Mills.  609 


A  distinctly  different  type  of  ventilating  and 
humidifying  apparatus,  whereby  the  air  is  forced 
through  a  system  of  air  ducts  or  trunks,  is  made  by 
Messrs.  Matthews  &  Yates  Ltd.,  of  Swinton,  and 
Messrs.  James  Howorth  &  Co.  Ltd.,  Farnworth. 
Both  systems  are  successful  ventilating  appliances 
and  they  leave  little  or  nothing  to  be  desired  so  far 
as  humidification  is  concerned.  Both  systems  are 
suitable  for  spinning  mills  as  well  as  weaving 
sheds. 

An  illustration  of  the  apparatus  of  Messrs. 
Matthews  &  Yates  Ltd.  is  shown  on  plate  xx,  and 
that  of  Messrs.  James  Howorth  &  Co.  Ltd.  on 
page  610  and  plate  xxi. 

Ventilation  of  Spinning  Mills. 

Spinning  mills  present  considerable  difficulties 
in  the  way  of  successful  ventilation.  To  reduce  the 
amount  of  carbon  dioxide  is  an  easy  matter,  but  to 
produce  suitable  conditions  for  spinning  is  not 
so  easy. 

For  successful  spinning  the  air  must  be  moist, 
but  not  too  moist.  If  it  be  too  dry  the  yarn  is 
weakened,  and  spinning  becomes  difficult,  with  result- 
ing bad  yarn.  On  the  other  hand,  if  the  moisture 
be  in  too  great  quantity,  there  is  trouble  with  the 
roller  laps,  and  a  very  considerable  danger  of  the 
finer  parts  of  the  spinning  machinery  and  the  rollers 
rusting,   a  condition  absolutely  fatal  to  spinning. 

M2 


Ventilation  of  Spinning  Mills.  6 1 1 

Again,  on  certain  days,  unless  the  air  be  filtered,  the 
yarn  would  be  blackened  and  rendered  unsaleable. 

At  the  present  time  the  majority  of  spinning 
mills  are  ventilated  by  means  of  windows  which  may 
be  opened  or  closed  at  the  will  of  the  particular 
operatives  working  near  them.  The  writer  has  taken 
samples  of  air  from  a  large  number  of  spinning 
mills,  and  from  the  information  obtained  by  analysis 
the  following  conclusions  were  arrived  at: — 

ist. — That  a  large  air  space  in  a  spinning 
room  is  not  necessarily  a  condition  for  successful 
ventilation. 

2nd. — That  to  obtain  a  condition  approaching 
the  standard  laid  down  for  humidified  weaving  sheds 
it  will  be  necessary  to  employ  mechanical  power. 

The  reason  why  a  large  air  space  is  not  sufficient 
is  in  itself  explained  by  the  working  conditions  of 
the  spinning  rooms.  The  temperature  of  the  air  is 
very  frequently  over  90  degrees  Fah.,  even  in  winter; 
consequently  the  air  expired  from  the  lungs  is  no 
warmer,  or  lighter,  than  the  mill  atmosphere,  and 
thus  has  little  tendency  to  rise.  In  an  ordinary 
building,  heated  to  60  or  70  degrees  Fah.,  the  air 
given  off  from  the  lungs  is  25  to  35  degrees  higher, 
and  consequently  much  lighter.  In  the  spinning 
rooms  it  is  simply  a  case  of  stagnation. 


6 1 2      The  Chemistry  and  Practice  of  Sizing. 


APPENDIX  A, 

Flour  Milling, 

with 

Farina  and  Dextrin  commercially  considered. 


IN  a  work  of  this  kind  it  is  not  necessary  to  go 
exhaustively  into  the  making  of  flour  in  ancient 
times,  suffice  it  to  say  that  until  about  thirty  years 
ago  the  process  consisted  principally  of  the  scouring 
of  the  wheats  through  wire  gauze  sieves,  some  flat 
and  other  cylindrical,  and  the  reduction  of  the 
cleaned  wheat  to  flour,  and  to  various  sizes  of  bran, 
by  grinding  between  horizontal  mill-stones,  specially 
cut  or  grooved  so  as  to  have  a  shearing  action  on 
the  wheat,  and  as  little  attrition  on  the  interior  of 
the  wheat  berry  as  possible. 

An  exception  to  this  method  of  manufacture 
must,  however,  be  made  in  favour  of  Hungary. 
In  that  country,  a  variety  of  wheat  is  grown  which 
is  exceedingly  rich  in  gluten,  but  is  so  hard  that  to 
grind  by  mill-stones  reduced  the  whole  to  a  sharp 


Flour  Milling. 


613 


powder,  the  branny  coat  of  the  wheat  being  inextric- 
ably mixed  with  the  floury  particles,  and  a  flour 
produced  both  unsightly  in  appearance  and  unpleasant 
in  flavour  and  texture.  Thus,  out  of  the  richest 
wheat  in  the  world,  one  of  the  poorest  flours  was 
produced.  The  Hungarian  millers,  however,  grad- 
ually evolved  a  new  system  of  treatment  of  the 
grain  by  reducing  it  by  gentle  breaking  up  between 
grooved  rollers.  This  process  of  reduction  was 
repeated  five  or  six  times,  the  first  reduction  opened 
the  wheat,  and  shook  the  interior  of  the  grain,  dis- 
lodging large  particles.  These  were  then  sorted 
by  horizontal  sieves,  and  each  division  subjected  to 
air  currents  drawn  through  the  semolina  as  it  fell 
from  stacje  to  sta^e.  At  each  reduction  these 
processes  were  repeated,  until  at  last  the  wheat  was 
divided  into  various  sizes  of  granular  semolina 
(resembling  various  grades  of  sugar)  on  the  one 
hand,  and  various  grades  of  wheat  offals  (such  as 
bran,  coarse  and  fine  sharps,  and  the  germ  of 
the  wheat)  on  the  other.  For  a  time,  the 
purified  semolina  was  reduced  to  flour  by  mill- 
stones, but  their  action  destroyed  the  granular 
character  of  the  flour,  and  they  were  discarded 
in  favour  of  smooth  rollers  capable  of  the  nicest 
regulation.  In  this  manner,  the  finest  flour  in 
the  world  was  produced,  a  flour  which  has  never 
been  surpassed,  and  which  for  a  long  time  was 
not    even    distantly   approached    by   any  other. 


6 14      The  Chemistry  and  Practice  of  Sizing. 

Austrian,  or  more  correctly  Hungarian,  flour 
gained  a  world-wide  fame,  the  mills  at  Buda- 
Pesth,  and  other  places  on  the  Danube,  were 
gigantic  in  size,  beautiful  in  structure,  and 
exceedingly  prosperous  commercially.  But  the 
old  adage,  11  Pride  goes  before  a  fall,"  came  true 
here  as  in  so  many  other  instances,  for,  in  the 
fulness  of  their  heart,  they  opened  their  doors  and 
exhibited  all  their  processes  to  a  large  excursion  of 
millers  and  milling  experts,  organised  by  an  eminent 
English  milling  engineer,  and  this  party,  including 
as  it  did,  the  brightest  men  of  Great  Britain  and 
America,  mastered  on  the  spot  the  whole  system  of 
Hungarian  milling.  The  next  thing  was  to  apply 
their  knowledge  to  the  wheats  they  were  themselves 
treating.  These,  it  is  true,  differed  in  many  cases 
from  Hungarian,  but  were  still  workable  on  that 
system. 

The  Americans  were  the  first  in  the  field  with 
their  modified  system,  quickly  followed  by  England, 
and  within  ten  years,  the  Hungarian  methods  had 
been  so  simplified,  the  construction  of  the  machines 
so  improved,  and  the  processes  rendered  so  com- 
pletely automatic  that  many  of  the  largest  Austrian 
mills  were  re-constructed  entirely  by  English 
engineers.  The  North-west  of  America,  including 
the  United  States  and  Canada,  produces  wheat 
closely  resembling  the  hard  Hungarian,  and  of  this 
immense  district,  Minneapolis,  in  Minnesota,  is  the 


Flour  Milling. 


615 


centre.  There  has  been  created  a  milling  industry 
equal  to,  and  parallel  with,  that  of  Buda-Pesth.  The 
huge  mills  there  are  driven  entirely  by  water,  a 
large  canal  above  the  falls  of  St.  Paul  taking 
sufficient  water  for  all  the  mechanical  processes 
required  by  the  city  for  both  milling  and  electrical 
purposes. 

But,  besides  the  gradual  reduction  of  the  wheat 
by  roller  processes,  there  have  gone  on  alongside  it 
other  improvements  in  the  cleaning  and  conditioning 
of  the  wheat,  of  almost  equal  importance.  As  before 
stated,  the  instruments  used  for  the  cleaning  of  the 
wheat  were  primarily  two: — 

The  Sieve  or  Screen,  and  Fan. 
These  were,  however,  of  little  use  in  dealing  with 
the  various  wheats  dumped  on  the  British  markets 
from  India,  Syria,  Egypt,  Chili,  the  Argentine,  &c, 
for  it  is  a  notable  fact  that,  wherever  the  Anglo- 
Saxon  has  settled,  from  that  country  comes  clean 
wheat,  unmixed  with  soil  or  stones,  thus  all  North- 
American,  Australian,  New  Zealand,  or  our  native 
wheats,  come  to  market  comparatively  pure  and  clean, 
whilst  from  Kurachee  we  get  10  per  cent,  of  fine 
grey  sandy  mud  deposited  by  the  Indus,  from  Bom- 
bay we  get  from  5  to  15  per  cent,  of  sticky  black 
clay,  from  Jubbulpore  small  stones,  from  Calcutta 
all  kinds  of  mineral  impurities,  from  Syria,  small 
stones  and  bits  of  iron  ore,  from  Egypt  the  Nile 


6 1 6       The  Chemistry  and  Practice  of  Sizing. 

mud  is  largely  sent  with  both  wheat  and  beans,  and 
from  Chili  some  of  the  wheats  evidently  trodden 
out  by  oxen  are  gathered  from  the  quartzy 
threshing-floor,  and  our  teeth  set  on  edge  by  eating 
bread  as  gritty  as  if  so  much  ground  glass  had  been 
added  to  the  flour. 

The  difficulty  the  English  miller  has  had  to  face  is 
therefore  a  very  great  one;  it  is,  howT  to  produce  an 
article  paramount  of  importance,  both  as  to  regu- 
larity of  colour,  flavour,  cleanliness,  and  glutinous 
strength,    out    of   materials  so  diverse  in  colour 
and    hardness,    and    so    loaded    with  impurities. 
Different  classes  of  wheat  may  also  at  one  time  glut 
the  market,  whilst  at  another  they  may  completely 
disappear,  in  some  cases  for  years  together.     It  is 
the  necessity  of  so  blending  and  treating  these 
varieties  of  wheat  as  they  successively  arrive,  and 
of  making  the  business  commercially  successful,  that 
has  rendered  British  milling  one  of  the  most  anxious 
and  unremunerative  of  our  trades,  and  one  which 
constantly  racks  the  minds  of  millers,  managers,  and 
experts.    For  we  must  remember  that  in  this  article  it 
is  not  the  analytical  chemist  and  the  manufacturer 
alone  whom  the  miller  has  to  satisfy,  but  the  whole 
population  are  daily,   nay  incessantly,  testing  his 
products  by  the  infallible  processes  of  mastication, 
taste,  smell,  and  digestion,  and  all  his  judges  from 
childhood  to  old  age,  are  capable  of  forming  and 
expressing  a  sound  opinion  on  the  matter. 


Flour  Milling. 


617 


Wheat  Cleaning  and  Conditioning. — The 
first  process  in  the  cleaning*  of  wheat  is  to  free  it 
from  such  impurities  as  straws,  stones,  lumps  of 
dirt,  &c.  For  this  purpose  it  is  put  through  a 
separator  and  scourer.  The  separator  consists  of  a 
series  of  three  sieves  placed  one  above  the  other,  and 
moving  to  and  from  at  a  very  rapid  rate,  the  sieves 
being  inclined  at  about  33  degrees.  This  shaking 
action  and  inclination  keeps  the  grain  moving  rapidly 
downwTards.  The  sieves  are  usually  of  perforated 
zinc  or  steel,  the  top  sieve  removes  sticks,  straws, 
lumps  of  dirt,  stones,  &c,  which  are  larger  than  a 
grain  of  wheat,  and  delivers  them  to  the  rubbish  bag. 
The  wheat  then  passes  over  another  perforated  plate 
with  holes  sufficiently  large  to  allow  everything 
smaller  than  a  grain  of  wheat  to  pass  through,  and 
thus  the  wheat  is  cleared  of  dust,  small  seeds,  and 
pellets  of  clay  and  earth. 

The  wheat  then  proceeds  to  a  steel  cylinder 
perforated  as  in  the  previous  case  but  provided  with 
beaters  or  brushes  run  at  a  great  speed,  and  by 
scouring  and  attrition  some  of  the  remaining  particles 
of  earth  are  removed  by  fans,  and  carried  to  the 
dust-collectors  or  stive  rooms. 

Of  late  years  the  great  importance  of  absolutely 
clean  wheat  has  induced  most  millers  to  wash  their 
wheats.  Some  wheats,  such  as  English,  Californian, 
Australian,  and  American  winter,  are  sufficiently 
clean  without,  but  almost  all  others,  both  on  account 


618       The  Chemistry  and  Practice  of  Sizing. 


of  their  extreme  hardness  and  also  because  they 
come  so  dirty,  require  washing.  This  is  done 
after  cleaning  as  before  described.  Some 
wheats  require  very  rapid  treatment,  being  simply 
rushed  through  the  water  by  centrifugal  action, 
but  others  require  longer  immersion.  Both  are 
however,  after  washing,  carried  to  a  wheat  whizzer, 
a  machine  very  similar  in  principle  and  action  to 
the  hydro-extractors  used  by  printers,  bleachers,  and 
dyers,  to  clear  their  cloth  or  yarn  of  superfluous 
moisture. 

The  wheats  are  afterwards  blended,  and,  after 
lying  together  for  some  time  to  assimilate,  are  passed 
through  a  drying  or  tempering  process.  This  consists 
in  allowing  the  wheat  to  proceed  down  the  outside  of 
a  cylindrical  or  a  square  tube  covered  both  inside 
and  out  with  perforated  metal,  or  with  wire  gauze. 
Through  the  wheat,  which  is  constantly  descending 
by  its  own  weight,  is  driven  by  fans,  a  stream  of  hot 
dry  air,  prepared  in  special  chambers  filled  with  coils 
of  copper  tubes  constantly  heated  by  steam,  and 
thus  the  whole  mass  to  be  treated  becomes  of  one 
uniform  degree  of  hardness  and  is  at  once  ready 
to  be  broken  up  by  the  roller  mills  as  already 
described. 

Having  described  in  a  general  way  the  evolution 
of  modern  methods  of  corn  milling,  we  must  now 
devote  a  short  space  to  the  consideration  of  our 
wheat  supplies. 


Flour  Milling.  619 

The  subjoined  table  gives  the  percentage  of  our 
wheat  imports  from  the  chief  sources  of  supply 
during  the  last  quinquennium  : — 


.  Country. 

1900. 
per  cent. 

1901. 
per  cent. 

1902. 
per  cent. 

I903. 
per  cent. 

1904. 
per  cent. 

19*0 

8'2 

4'2 

12*2 

i8-5 

Rou  mania  

o-8 

o'5 

2*2 

27 

''3 

Russia   

4*6 

2'5 

6'i 

14*8 

20'I 

United  States   

58-2 

66-2 

60*2 

40"0 

157 

Other  Foreign  Countries... 

3'3 

37 

3'3 

Total  Foreign  Countries  ... 

877 

807 

76-4 

73'° 

6o-8 

6-i 

3'9 

96 

Canada  

8'i 

8'5 

ir3 

124 

India  

3'3 

8'2 

14*6 

2  I  '6 

Other  British  Possessions 

I  '2 

i*4 

0'2 

0-4 

Total  British  possessions... 

12*3 

!9"3 

23-6 

27*0 

39'2 

Roughly  speaking  it  may  be  stated  that  our 
total  wheat  (and  flour)  imports  are  equal  to  about 
three  times  the  quantity  of  wheat  grown  in  the 
United  Kingdom  and  that  the  proportion  of  im- 
ported to  home-grown  grain  shows  a  tendency  to 
increase.  As  will  have  been  noticed  from  the  above 
statistics  the  United  States  in  1904  lost  its  pre- 
eminence among  our  contributories  and  sank  to  the 
fourth  place  on  the  list,  whilst  India  rose  to  the 
first  place  (supplying  25*5  million  cwts.  out  of  118 
million  cwts.),  closely  followed  by  Russia  and 
Argentina,   with    237    and    21*8    million  cwts. 


620      The  Chemistry  and  Practice  of  Sizing. 

respectively.  Australia  also  in  1904  sent  the 
largest  quantity  received  thence  up  to  that  time 
(1 1*3  million  cwts.),  as  against  practically  nil  in  1903. 

Taking  the  last  four  seasons  the  wheat-importing 
countries  of  the  world  require  some  64  or  65  million 
quarters  of  wheat  per  annum,  of  which  about  26  or 
27  millions  are  required  by  the  United  Kingdom, 
about  8  or  9  millions  by  Germany,  6  by  Belgium, 
and  4  to  6  by  Italy.  Against  these  worlds 
requirements  may  be  set  the  following  surpluses: — 


1905-6. 

1904-5. 

1903-4. 

(111 

thousands  of 

quarters — 1 

qr=480  lbs.) 

Russian  and  Danubian  Countries... 

30,000 

29,000 

24,500 

U.S.A  

12,500 

5>5°° 

M,325 

Canada   

2;75° 

3>25° 

Argentina   

I3,000 

13,000 

9>5°° 

India   

3>25° 

9>5°° 

7,200 

4,000 

4,5°° 

3>5°° 

Miscellaneous  

I,000 

t,45° 

1,850 

Total  

69,000 

65,700 

64>I25 

Of  the  above  wheat-exporting  countries  it  may 
be  mentioned  that  the  Australasian  crop  (while 
excellent  in  quality)  is  only  a  small  one,  though 
gradually  improving  in  this  respect: — 1899,  5,500; 
1900,  6,900;  1 901,  5,400;  1902,  2,500  (famine 
year);  1903,  10,100;  1904,  7,900;  1905,  9,500; 
1906,  9,000  (estimated)  thousands  of  quarters. 

The  Argentine  crop  is  a  large  one  and  may  in 
time  become  immense,  as  there  are  wheat  lands 


Flour  Milling, 


gently  sloping  to  the  Parana  and  other  rivers, 
capable  of  producing,  under  good  cultivation,  enough 
wheat  for  the  whole  human  race,  whilst  the  rivers 
are  open  for  1,500  miles  inland  for  vessels  capable 
of  carrying  800  tons.  This  crop  has  fairly  constantly 
increased,  and  when  a  good  one,  is  an  important 
factor  in  preventing  prices  running  away  at  a  critical 
period  of  the  cereal  year  (February,  March  and 
April),  wThen  also  India  and  Australia  are  helping  to 
relieve  the  situation. 

The  following  table  (taken,  as  are  many  of  the 
statistics  quoted,  from  the  ''Statist")  giving  the  totals 
of  Argentine  wheat  crops  and  exports  for  the  past 
few  years  is  interesting  : — 


1899    12,750,000  qrs.     ...      9,750,000  qrs. 

1900    8,250,000  qrs.     ...      4,150,000  qrs. 

1901    7,000,000  qrs.     ...      3,000,000  qrs. 

1902    12,500,000  qrs.     ...      8,000,000  qrs. 

1903    15,500,000  qrs.     ...     r  1,250,000  qrs. 

1904    1 8,500,000  qrs.     ...     13,000,000  qrs. 

1905    16,500,000  qrs.     ...     13,000,000  qrs. 

(1  qr.  =  480  lbs.) 

1906    16,500,000  qrs.  (estimated). 


The  average  world's  wheat  crop  for  the  last  four 
years,  1903- 1906,  has  been  about  417  million  qrs. 
and  of  this  quantity  U.S.A.  has  produced  80,  Russia 
(alone)  77,  France,  42,  India,  39,  Hungary  (including 
Slavonia  and  Croatia)  21^,  Italy  19I,  Germany  17^, 
Argentina  i6|,  Spain  12^,  Canada  11^,  Roumania 
\o\,  Japan  \o\,  Australia  9,  United  Kingdom  6\, 
million  quarters  respectively  on  an  average. 


622      The  Chemistry  and  Practice  of  Sizing. 

The  wheat  crops  are  reaped  as  early  as  the  end 
of  May  in  Kansas  and  Texas,  and  as  late  as  October 
in  the  new  North-western  States  and  N.W.  Canada. 
The  Russian  and  European  crops  generally  are 
reaped,  like  our  own,  from  the  beginning  of  July  to 
the  end  of  September.  Many  of  the  Northern 
States  of  America,  Canada,  and  Russia,  have,  from 
April  to  the  beginning  of  July,  two  crops  of  wheat 
growing  side  by  side.  First,  the  Winter  wheat  sown 
the  previous  autumn  and  well  advanced  when  spring 
arrives;  and  secondly,  the  Spring  wheat,  which  is 
cultivated  in  the  colder  districts  and  cannot  with- 
stand the  rigour  of  the  winter.  The  latter  is  not 
sown,  therefore,  till  the  frost  is  out  of  the  ground, 
say  about  the  middle  of  April,  and  cannot  mature 
till  late  in  the  season.  The  danger  to  this  crop 
arises  from  premature  frosts  before  the  wheat  is 
ripe,  a  single  night  sometimes  ruining  the  most 
brilliant  prospects.  The  average  relative  weights 
of  these  crops  in  America  are  as  three  of  Winter  to 
two  of  Spring  wheat. 

After  the  harvest  farmers  naturally  desire  to 
market  their  produce  quickly  for  monetary  reasons, 
and  especially  so  in  Russia  and  the  northern  parts 
of  America,  because  the  rivers,  lakes,  and  the  Black 
and  Baltic  seas  are  often  closed  by  ice  from  about 
the  middle  of  November  to  the  following  April, 
Thus  the  wheat  which  is  intended  to  be  sold  is 
rushed  to  market  from  all  quarters  during  September 


Flour  Milling. 


623 


and  October,  and  often,  as  a  consequence,  in  or 
about  October  the  lowest  price  is  reached  for  the 
whole  cereal  year. 

After  October  the  shipments  from  Argentina, 
India  and  Australia  are  dwindling-  away  and  for  a 
period  of  about  three  or  four  months  the  world's 
market  is  left  in  the  hands  of  Russia  (with 
Roumania)  and  America  (with  Canada).  From 
February  onwards  the  newly-reaped  Argentine, 
Australian  and  Indian  crops  come  round  again,  and 
by  their  relative  abundance  or  deficiency  modify 
the  situation  until  July  or  August.  About  this 
period  we  are  favoured  with  estimates  of  the 
various  wheat  crops  reaped  or  about  to  be  reaped 
in  Europe  and  America,  and  also  with  the  estimated 
acreage  sown  once  more  in  Australia,  Argentina  and 
India.  It  is  therefore  generally  possible  by  about 
the  middle  of  September  to  forecast  approximately 
what  will  be  the  world's  surpluses  and  requirements 
during  the  ensuing  twelve  months  and  to  form  a 
fairly  accurate  idea  as  to  the  general  trend  of  prices 
during  the  new  campaign. 

As  by  about  this  time  or  a  little  later  (say  the 
middle  of  October),  the  size  and  quality  of  the 
potato  crops  of  Europe  are  known  and  tested,  and 
the  manufacture  of  the  latter  into  farina  is  then  in 
full  progress,  in  order  that  that  article  may  also  be 
got  to  the  seaboard  before  the  close  of  inland 
navigation,  October  is  the  most  favourable  period  of 


624      The  Chemistry  and  Practice  of  Sizing. 

the  year  for  manufacturers,  bleachers,  and  printers 
to  contract  for  their  yearly  requirements. 


The  " North  Western  Miller"  gives  the 
following  as  a  list  of  the  months  of  harvest  in  the 
chief  wheat-growing-  areas: — 

January.  ..Australia,  New  Zealand,  Chili,  and  Argentine. 

February  and  March. — East  India  and  Upper  Egypt. 

April  Lower  Egypt,    Syria,    Cyprus,    Persia,  Asia  Minor, 

India,  Mexico,  and  Cuba. 

May  Algeria,    Central    Asia,    China,    Japan,  Morocco, 

Texas,  and  Florida. 

June  .Turkey,  Greece,  Italy,  Spain,  Portugal,  S.  France, 

California,  Oregon,  Louisiana,  Mississippi,  Alabama, 
Georgia,  Carolina,  Tennessee,  Virginia,  Kentucky, 
Kansas,  Arkansas,  Utah,  Colorado,  and  Missouri. 

July   Roumania,    Bulgaria,    Austra-Hungary,    South  of 

Russia,  Germany,  Switzerland,  France,  South  of 
England,  Nebraska,  Minnesota,  Wisconsin,  Iowa, 
Illinois,  Indiana,  Michigan,  Ohio,  New  York,  New 
England  and  Upper  Canada. 

August  Belgium,  Holland,  Great  Britain,  Denmark,  Poland, 

Lower  Canada,  Columbia,  and  Manitoba. 

September  and  October. — Scotland,  Sweden,  Norway  and  North 
of  Russia. 

November ...Yexw,  and  South  Africa. 

December . . .  Burmah, 


Farina  and  Dextrin. 


625 


FARINA  AND  DEXTRIN 

COMMERCIALLY  CONSIDERED. 

A  short  description  of  the  manufacture  of  farina 
has  already  been  given  in  the  chapter  dealing-  with 
the  starches.  With  a  view  to  giving  further  details 
not  necessarily  of  interest  to  sizers  alone,  the  subject 
has  been  left  to  be  more  fully  dealt  with  in  the 
appendix.  In  the  preparation  of  farina  the  following 
processes  are  involved.  After  careful  washing,  the 
potatoes  are  reduced  to  a  fine  pulp  in  a  rasping 
machine.  This  pulp  is  afterwards  washed  through 
fine  sieves,  the  starchy  matter  being  carried  in 
suspension  in  the  washings  and  deposited  in  settling 
tanks  as  "raw  starch."  The  raw  starch  contains 
various  impurities,  such  as  cellulose,  albuminoids, 
fragments  of  potato,  &c.  By  repeating  the  process, 
and  using  sieves,  some  of  which  have  a  revolving 
and  others  a  horizontal  motion,  most  of  these 
impurities  are  removed  and  the  milky  liquor,  after 
standing  in  settling  tanks,  deposits  its  starch.  To 
hasten  the  separation  of  the  starch  small  quantities 
of  alum  or  of  sulphuric  acid  are  used.  The  former 
has,  however,  the  disadvantage  of  coagulating  the 
albumen  and  to  that  extent  contaminating  the  starch, 
whilst  the  latter  has  a  slight  chemical  action  on  the 
starch  itself,  and  is  also  difficult  of  neutralisation. 
When  the  potatoes  are  more  or  less  affected  by 

N2 


626      The  Chemistry  and  Practice  of  Sizing. 


disease,  or  are  touched  by  frost,  great  difficulty  is 
experienced  in  effecting  a  speedy  and  a  complete 
precipitation  of  the  starch,  and  various  reagents, 
such  as  bisulphite  of  lime,  sulphurous  acid,  or  caustic 
soda  solution,  may  be  called  into  use.  Once  freed 
from  bacterial  impurities,  however,  the  usual  routine 
may  be  followed. 

After  the  starch  has  settled,  the  supernatant 
liquor  is  drawn  off,  and  the  starch  re-washed.  It  is 
afterwards  dried  by  means  of  a  centrifugal  washing 
machine  and  also  by  exposure  to  the  air. 

The  stage  is  now  reached  at  which  either  the 
process  of  conversion  into  dextrin  (by  the  action  of 
heat  and  the  use  of  hydrochloric  or  nitric  acid),  or 
into  glucose  (starch-sugar)  is  entered  upon,  or  the 
starch  is  ground  up  and  further  dried  in  a  heated 
chamber. 

Potatoes  contain  a  variable  quantity  of  starch,  but, 
on  the  average,  factory-potatoes  (fabrikkartoffeln) 
contain  18  per  cent,  and  by  careful  manipulation 
and  good  equipment  17  per  cent,  of  dry  starch 
(trockene  starke)  can  be  obtained.  Of  this  quantity 
about  14*5  parts  will  be  commercial  farina  (of 
superior  and  prima  qualities)  and  2*5  parts  will  be 
by-products  (schlammstarke  and  schlamm).  The 
commercial  article  should  not  contain  more  than  20 
per  cent,  (usually  17  to  20  per  cent.)  of  moisture, 
and  chemical  examination  shows  it  to  contain  about 
o*2  to  o'5  per  cent,  of  ash,  0*25  per  cent,  of  albumen 


Farina  and  Dextrin.  627 

and  0*055  Per  cent-  of  fatty  matter.  It  should  be 
free  from  acid,  and  practically  free  from  specks 
(stippen),  whether  due  to  the  presence  of  fragments 
of  peel,  chip,  or  fungoid  growth.  The  size  of  the 
microscopic  granules  varies  from  o'ooS  mm.  in  the 
lowest  grades  to  0*0355  mm.  in  the  very  highest 
grades  of  farina. 

In  the  conversion  into  dextrin  about  80  to  88 
parts  of  dextrin  are  obtained  from    100  parts  of 
farina  and  the  usual  difference  in  price  between  the 
same  firm's  make  of  farina  and  dextrin  is  from  £2 
to         per  ton.      Chemically  examined  the  com- 
mercial article  may  contain  from  20  to  75  per  cent,  of 
dextrin  (usually   from  45  to  65  per  cent.),  this 
amount   being    frequently   arranged    to   suit  the 
requirements  of  the  user.     In  water-free  samples  of 
dextrin  as  high  as  80  per  cent,  of  dextrin  has  been 
found  in  the  commercial  white  dextrin,  and  as  high 
as  97  per  cent,  in  the  yellow.    The  water  contained 
is  from  10  to  12  per  cent.,  dextrose  2  to  7  per  cent, 
(usually  about  5  per  cent.),  ash  0*5  per  cent.,  the 
balance  consisting  of  unconverted  starch.     As  to 
acidity,  about  100  grams  of  dextrin  usually  require 
3  c.c.  (or  from  1  to  6  c.c.)  of  normal  alkali  solution 
for  neutralisation.    Newly  made  yellow  dextrin  has 
a  tender   greenish    undershade,  but  with  age  it 
turns  reddish. 

Farina  is  no  longer  made  in  England,  but  a 
variety  of  dextrin    (known  as    " British  Gum"), 


628      The  Chemistry  and  Practice  of  Sizing. 


manufactured  from  mixtures  of  starches  (sago-flour, 
tapioca-flour,  maize  starch,  and  lower  qualities  of 
farina),  is  made  in  works  chiefly  situated  in  and 
around  Manchester. 

For  the  sake  of  comparison  with  the  German 
potato  crop  statistics,  given  below,  it  may  be  of 
interest  to  state  that  for  the  period  1896- 1900  the 
average  British  crop  was  5,401,764  tons  per  annum 
(i.e.,  about  one-eighth  the  size  of  the  German  crop), 
whilst  the  yield  per  acre  for  the  period  1890-99  was 
4-59  tons. 


The  German  Potato  Crops: — 


Season. 

Thousands  of 

Crop  in 

Tons 

Exports  from  Germany  in  tons. 

Acres  under 
Cultivation. 

Thousands  of 
(English)  Tons. 

per 
Acre. 

Farina  (and 
Potato  Flour). 

Dextrin. 

7,533 

37,i9T 

4'94 

29,939 

8,622 

1896 

7,540 

31,820 

4*22 

33,402 

10,851 

1897 

7,577 

33,244 

4*39 

1 3,9*9 

9,721 

T898 

7,609 

36,142 

475 

17,055 

7,958 

1899 

7,735 

37,880 

4-90 

33^3^5 

9,827 

19OO 

7,95° 

39,946 

5-02 

21,449 

10,007 

19OI 

8,198 

47,921 

5-85 

25,048 

10,977 

1902 

8,004 

42,778 

5'34 

45,237 

13,827 

1903 

7,997 

42,226 

5-28 

27,995 

13,855 

1904 

8,  I2T 

35,7i6 

4-40 

1 7,262 

11, 936 

T9°5 

8,192 

47,562 

5-8i 

In  1897-8  the  total  quantity  of  German  farina 
was  778,543  bags,  and  of  dextrin  189,588  bags. 
Although,  in  this  respect,  official  statistics  of  later 
date   are    not   obtainable,   it  is  believed  that  in 


Farina  and  Dextrin. 


629 


favourable  years  these  figures  are  considerably 
exceeded,  possibly  by  50  per  cent. 

Farina  is  used  more  extensively  as  a  sizing 
ingredient  in  Germany,  taking  into  consideration 
the  size  of  the  cotton  industry  in  that  country,  than 
in  England,  because  sago-flour,  tapioca-flour,  and 
maize-starch  are  unable  effectively  to  compete  owing 
to  the  heavy  import  duties  on  these  articles  in  the 
former  country.  The  quantity  of  farina  exported 
from  Germany  bears  a  variable  relation  to  the 
quantity  made  there,  being  as  much  as  50  per  cent, 
when  prices  are  low,  whilst  it  is  much  less  when 
high  prices  rule.  Of  the  exports  of  farina  and 
dextrin  from  Germany  the  United  Kingdom  takes 
by  far  the  largest  quantity  (sometimes  more  than 
one  half),  the  next  best  customers  being  (in  the 
order  given), 

(1)  For  farina: — Spain,  America,  Denmark, 
Italy,  and  Switzerland. 

(2)  For  dextrin: — America,  Austria- Hungary, 
Italy,  Spain  and  Switzerland. 

If  we  look  at  the  question  of  British  starch 
imports,  we  find,  taking  an  average  of  years,  about 
89  per  cent,  come  from  three  countries,  viz.,  37^ 
per  cent,  from  Germany,  26  per  cent,  from 
Holland,  and  25J  per  cent,  from  U.S.A.  Of  the 
American  supplies  by  far  the  greater  part  consists 
of  maize  starch,  of  the  Dutch  of  farina  (potato 
starch),  and  of  the  German  of  farina  and  rice  starch, 


630      The  Chemistry  and  Practice  of  Sizing. 

About  85  to  90  per  cent,  of  our  imported  dextrin 
comes  from  Germany,  about  6  to  10  per  cent,  from 
Holland,  and  the  remainder  from  U.S.A.  and 
miscellaneous  sources. 

The  relative  importance  of  various  countries  as 
dextrin  users  is  given  to  some  extent  by  an  analysis 
of  the  distribution  of  Germany's  exports  of  dextrin. 
Great  Britain  41^  per  cent.,  U.S.A.  and  Austria- 
Hungary  each  13^  per  cent.,  Spain  5^  per  cent, 
Italy  and  Switzerland  each  4§  per  cent.  It  should, 
however,  be  noted  that  this  does  not  take  into 
account  the  quantity  of  German-made  dextrin  used 
in  Germany,  whilst  in  U.S.A.  maize  starch  dextrin 
is  also  used,  and  in  England,  besides  the  imported 
dextrins,  a  certain  quantity  of  English-made  dextrin 
and  soluble  starch  (prepared  from  various  starches 
and  starch  mixtures)  is  used. 

As  will  already  have  been  noticed  from  the 
foregoing  table  the  acreage  under  potato  cultivation 
in  Germany  during  the  last  decade  showed  a  gradual 
and  constant  increase  up  to  1901,  when  the  greatest 
acreage  was  reached,  and  since  which  time  there 
has  been  but  slight  variation.  The  yield  per  acre 
has  also  been  much  larger  during  the  last  quin- 
quennium than  in  1895-99,  especially  when  it  is 
considered  that  the  low  result  in  1904  was  due  to 
very  severe  drought. 

Two-thirds  of  the  area  under  potatoes  is  in 
Prussia  (chiefly    in    the    provinces    of  Schlesien. 


Farina  and  Dextrin. 


631 


Brandenburg,  Posen,  and  Pomerania).  Outside 
Prussia  the  most  important  potato  districts  are 
Bavaria,  Saxony,  and  Wiitemberg.  According  to 
Dr.  Behrend  ("  Deutschlands  Kartoffelerzeueune 
und  Verbrauch  in  Gegenwart  und  Zukunft")  the 
distribution  of  a  German  potato  crop,  of  say  43 
million  tons,  would  be  about  as  follows  : — 

Manufacture  of  Potato  Spirit    2*5  million  tons 

Manufacture  of  Farina  and  of  Farina 

Products  (Dextrin,  Glucose,  &c.)  1*4  ,, 

Used  for  Seed  purposes    5-2.  ,, 

Loss  by  Disease  (10  per  cent.)   4*3  ,, 

Human  Consumption   12*0  „ 

Pig-feeding,  Szc   17-6  ,, 

The  shipments  of  farina  and  dextrin  to  this 
country  are  usually  much  the  heaviest  in  October 
and  November,  not  only  on  account  of  the  dwind- 
ling of  old  stocks  at  the  various  distributing  centres 
but  also  that  towards  the  end  of  November  internal 
navigation  is  often  interfered  with  in  Germany  and 
Holland  by  ice,  involving  higher  internal  freight 
charges.  The  makers  are  also  then  working  at  high 
pressure  on  the  new  seasons  produce,  and  are 
anxious  to  dispose  of  a  good  portion  of  their  manu- 
factured products  as  early  as  possible.  A  good 
proportion  of  the  users  in  this  country  contract  for 
their  year's  requirements  when  the  new  season's 
price  of  the  B.K.M.F.  farina  (a  mark  of  farina 
made  originally  in  Baden,  but  now  at  Ciistrin,  in 
Prussia),  and  other  equally  well-known  marks  of 


632       The  Chemistry  and  Practice  of  Sizing. 


farina  are  quoted,  usually  some  time  in  October  (or 
in  November,  when  the  crop  is  late),  as,  by  that 
time,  the  result  of  the  crop  is  almost  assured, 
providing  severe  frost  does  not  set  in  and  cause  a 
smart  advance,  as  in  1902,  or  disease  does  not 
manifest  itself,  especially  in  the  potatoes  stored  in 
pits  for  the  winter. 

Taking  a  number  of  years  with  cheap  autumn 
prices  it  may  be  stated  (almost  as  a  general  rule) 
that  the  prices  in  March,  and  later  months,  show  a 
very  considerable  advance  (as  in  1887,  1897,  1901, 
1902,  &c).  The  converse  proposition  that  high 
autumn  prices  are  followed  by  lower  spring  prices 
obtained  in  1871,  1888,  1891,  &c,  but  cannot  be 
relied  upon  to  the  same  extent.  In  this  connection 
the  attention  of  the  reader  may  be  drawn  to  the 
following  deductions  from  a  chart  published  by  the 
"  Deutschen  Starkeverkaufsgenossenschaft,"  in  Ber- 
lin, in  1905,  showing  the  fluctuations  in  the  price  of 
"  Prima"  farina  in  the  Berlin  starch  market  since 
i860.  From  this  chart  it  appears  that  the  highest 
and  lowest  prices  touched  were  from  44*5  marks  in 
December,  1871,  to  just  over  14  marks  in  November- 
December,  1895,  the  highest  price  being  more  than 
three  times  the  lowest.  Great  variations  in  price  of 
10  or  even  15  marks  {i.e.,  £5  to  £j  10s.  per  ton) 
have  taken  place  within  very  short  periods.  Thus 
between  August  and  December,  1871,  the  price  rose 
from  29*5  marks  to  44*5  marks,  and  between  July 


Farina  and  Dextrin. 


633 


and  December,  1892,  it  declined  from  36  marks  to 
18  marks  per  sack.  Maximum  prices  have  usually 
obtained  during  the  winter  months,  November  to 
March;  thus,  in  February,  1861,  40  m. ;  January, 
1868,  39*5  m. ;  December,  1871,  44/5  m. ;  March, 
1880,  36  m. ;  December,  1 891,  nearly  38  m.;  the 
prices  were  much  higher  than  in  the  preceding  and 
following  months.  Price-minima  have  also  shown 
a  predilection  for  the  winter  months,  as  in  the 
seasons  1884-5,  1885-6,  1893-4,  1895-6.  It  also 
appears  that  low  prices  have  ruled  for  longer  periods 
and  with  smaller  fluctuations  than  when  high  prices 
obtained.  Taking  quinquennial  periods  we  see  that 
the  general  tendency  has  been  for  lower  prices  and 
smaller  fluctuations: — 


Period. 

Minimum  Price. 

Maximum  Price. 

1860-1865 

230 

Marks. 

40*0 

Marks. 

1865-187C 

23*5 

55 

39*5 

55 

1870-1875 

24*1 

55 

44*5 

55 

1875-1880 

24*2 

55 

32*° 

55 

1880-1885 

16-5 

55 

36*0 

55 

1885-1890 

16*0 

55 

28-6 

55 

1890-1895 

l6"2 

55 

377 

55 

1895-1900 

55 

26-8 

55 

1900-1905 

14-8 

55 

28*2 

55 

DUTCH  FARINA. 
It  is  remarkable  how  widespread  potato  culture 
is  in  Holland,  158,732  hectares  {i.e.,  392,068  acres) 
out  of  a  total  of  931,834  hectares  (1  hectare  =  2 '4  7 


634       The  Chemistry  and  Practice  of  Sizing. 


acres)  being  under  potatoes  in  1904,  and  of  these 
26,529  hectares  (or  65,527  acres)  were  devoted  to 
the  culture  of  fabrik-hartoffeln,  i.e.,  potatoes  intended 
for  the  manufacture  of  farina,  dextrin  and  glucose. 
The  acreage  under  factory  potatoes  in  1905  was 
29,714  hectares,  and  in  1906,  27,238  hectares. 
Taking  all  Holland  in  1904,  the  crop  was  2,063,252 
English  tons,  or  5^  tons  per  acre,  whilst  for  factory 
potatoes  it  was  604,719  tons,  or  9*20  tons  per  acre. 
Under  the  most  favourable  conditions  and  in  isolated 
areas,  a  yield  of  as  much  as  nearly  16  tons  per  acre 
(40,000  kilos  pro  hectar)  has  been  obtained. 

The  districts  chiefly  devoted  to  the  cultivation 
of  factory  potatoes  are  known  as  the  "Veen- 
kolonien,"  or  turf  colonies,  of  Groningen  and 
Drenthe.  The  land  was  formerly  an  extensive 
peat-bog,  which  was  only  with  difficulty  brought 
under  cultivation  by  draining  the  land  by  means  of 
deep  canals  and  trenches,  stripping  the  surface  of 
peat  (for  fuel)  and  suitably  manuring  the  underlying 
soil.  These  tracts  are  known  as  "  Hohe  Veenen,"  or 
high  fens.  The  turf-cutting  was  begun  on  a  small 
scale  at  Groningen  in  the  eleventh  and  twelfth  cen- 
turies, but  the  commencement  of  the  first  colonies 
and  the  cultivation  of  the  peat-stripped  areas  dates 
from  the  thirteenth  and  fourteenth  centuries,  the 
turf  being  sent  in  boats  down  to  Groningen,  and 
there  sold  for  fuel,  whilst  the  town  manure  was  sent 
back  gratis,  and  in  1848  the  town  even  forbad  its 


Farina  and  Dextrin. 


635 


going  elsewhere.  Later,  however,  the  town  sold  the 
Kompost  to  the  settlers,  and  from  1862  to  1878  the 
sale  brought  in  27,000  florins  yearly.  This  form  of 
manuring  has  now  given  place  to  a  more  elaborate 
and  scientific  system,  and  to-day  the  turf-boats  go 
back  empty.  In  the  eighteenth  and  up  to  the 
middle  of  the  nineteenth  century  the  culture  of  corn, 
rape-seed,  and  mustard,  were  the  most  important, 
but  since  then  potato-culture  has  been  the  most  im- 
portant branch  of  agriculture,  and  potatoes  have 
been  exported  from  the  Veen-colonies  since  1778. 

Distilleries  for  potato-spirit  were  started  but  did 
not  prosper  in  the  land  of  gin,  and  Holland  kept  to 
its  corn  distilleries.  The  first  Dutch  farina  factory 
was  that  started  in  Muntendam  by  J.  A.  Boon  in 
1840,  but  it  was  short-lived.  He  was  followed 
shortly  afterwards  by  W.  A.  Scholton,  and  then  by 
numerous  others.  In  fact  so  keen  became  the 
rivalry  among  the  farina-makers  to  secure  the 
potatoes  that  the  growers  very  greatly  profited,  and 
ultimately  this  led  to  the  formation  of  the  "Eureka" 
potato-buying  combine  (Eureka  Verkoopscantor 
Ardappelmeel),  which,  from  the  start,  met  with  the 
antipathy  of  the  growers,  as  they  had  to  deliver  at  a 
price  fixed  by  the  "Eureka."  Enterprising  growers, 
therefore,  combined  in  self-defence  and  formed  the 
first  Co-operative  Ardappelmeelfabrik,  which  w7as 
followed  by  other  co-operative  mills  owned  by  the 
growers,  who  supplied  them  with  the  potatoes,  until 


636      The  Chemistry  and  Practice  of  Sizing. 

to-day  there  are  some  32  factories  (private,  company 
and  co-operative  mills),  the  majority  new,  well- 
equipped,  and  capable  of  dealing  with  a  large 
quantity  of  potatoes.  In  1904,  some  87,894 
(English)  tons  of  farina  were  made  in  Holland,  of 
which  68,745  tons  were  exported.  (In  addition 
to  farina,  some  factories  also  manufacture  dextrin 
and  glucose).  This  vast  quantity  of  farina  is  bought 
by  the  United  Kingdom,  the  United  States, 
Belgium,  Spain,  Italy,  Scandinavia,  and  the 
Colonies.  It  may  be  remarked  here,  that  most 
of  the  farina  sent  to  India  goes  by  Liverpool,  and 
through  the  medium  of  English  merchants.  The 
superior  qualities  made  by  the  best  of  the  Dutch 
factories  are  now  so  pure  and  good  as  scarcely  to 
leave  room  for  further  improvement,  whilst  the  old 
drawback  to  the  use  of  Dutch  farina — its  high 
percentage  of  moisture,  often  over  24  per  cent. — 
has  been  done  away  with  by  the  adoption  of 
improved  methods,  and  a  percentage  of  even  20  per 
cent,  is  now  rarely  met  with,  except  sometimes  at 
the  opening  of  the  new  season. 

SAGO  FLOUR. 

The  average  monthly  consumption  of  sago  flour 
in  Lancashire  in  1903  was  about  1,190  tons;  in  1904 
1,251  tons;  and  in  1905,  1,357  tons. 


"Sliver"  Dyeing. 


637 


APPENDIX  B. 

New  Process  of  Cotton  Dyeing. 


THERE  is  a  great  demand  for  a  more  uniform 
colour  in  dyed  cotton  than  can  be  produced 
either  by  dyeing  in  the  piece  or  by  dyeing  in  the 
form  of  hanks,  cops  or  bobbins. 

There  is  no  doubt  that  until  recently  the  best 
results  were  obtained  by  dyeing  raw  cotton,  but  this 
process  is  economically  unsatisfactory  for  several 
reasons.  In  the  first  place  all  the  wTaste  cotton  and 
the  dust  and  dirt  is  dyed,  and  in  the  second  place 
the  coloured  waste  is  practically  unsaleable. 

The  best  stage  in  which  the  dyeing  can  be 
carried  out  is  whilst  the  cotton  is  in  the  form  of 
" sliver."  In  this  stage  only  that  cotton  which  will 
be  spun  into  yarn  is  treated  and  there  is  therefore 
no  waste  of  dye  stuff. 

As  far  as  the  minutest  tests  can  be  made  it  has 
been  shown  that  "sliver"  dyeing  produces  an 
absolutely  perfect  and  uniform  colour  in  the  thread, 


638      The  Chemistry  and  Practice  of  Sizing. 

which  is  far  in  advance  of  any  other  form  of  dyeing. 
Every  fibre  is  dyed  through,  and  whether  the  yarn 
has  to  be  woven  into  plain  self-coloured  cloth  or 
used  for  borders  and  headings,  the  shade  is 
perfect. 

The  process  of  " sliver"  dyeing  has  been  per- 
fected, after  many  years  of  experiments,  by  Mr.  Dan 
Scholefield,  who  has  had  over  50  years'  experience 
as  a  practical  dyer.  It  is  past  the  experimental 
stage,  and  there  is  no  process  to  compare  with  it 
for  economy,  simplicity,  and  uniformity  of  shade, 
and  there  is  no  difficulty  in  the  spinning  operations 
after  dyeing. 

The  dyeing  machine  is  simple  in  construction, 
and  there  is  nothing"  to  get  out  of  order. 

The  possibilities  of  ''sliver"  dyeing  have  been 
greatly  increased  by  the  introduction  of  the  sulphur 
colours,  and  by  the  introduction  of  the  hyposulphite- 
soda  vat  process  of  indigo  dyeing.  These  valuable 
additions  to  the  dyes  employed  for  cotton  are 
specially  applicable  to  "sliver"  dyeing. 

Practically  every  description  of  dyeing  can  be 
carried  out  by  the  processes,  but  the  following  are 
the  most  suitable  classes  of  colours  to  employ : — 
Direct  colours,  sulphur  colours  and  indigo. 

From  what  has  been  said  it  will  be  apparent 
that  this  is  a  process  of  dyeing  which  can  be  carried 
out  by  the  cotton  spinner  only  and  not  by  the  dyer 
of  hanks  or  piece  goods. 


"Sliver'  Dyeing. 


639 


The  process  does  not  require  any  special  training 
on  the  part  of  the  spinner  as  it  is  absolutely 
mechanical  after  the  machine  is  working. 

It  will  be  at  once  appreciated  by  the  spinner 
how  evenness  of  shade  can  be  got  in  the  spun  yarn. 
If  there  is  any  variation  in  one  batch  of  dyed 
" slivers,"  the  next  lot  can  be  dyed  darker  or  lighter 
as  required.  As  it  is  customary  to  draw  from  six 
cans  at  the  first  draw  frame,  perfect  evenness  of 
shade  can  be  produced  in  the  final  spinning. 


640      The  Chemistry  and  Practice  of  Sizing. 


APPENDIX  C. 

Table  comparing  Beaitme 
and  Tzvaddell  ivith  Specific  Gravity 

together  with 
Percentage  Table  of  Common  Chemicals. 


PERCENTAGE  OF 

Beaume. 

Twaddell. 

Specific 
Gravity. 

Sul- 
phuric 

Spirits 
of 

Nitric 
Acid. 

1 

Caustic 
Soda 

S02  in 
Sodium 
Bisul- 

Acid. 

Salts. 

in  a  uii. 

phite. 

O 

O 

1,000 

0-9 

OI 

0*2 

O 

I 

I '4 

1,007 

1  '9 

1-5 

1 '5 

o#6i 

0*4 

2 

2  0 

1,014 

2-8 

2-9 

26 

1  20 

0-85 

3 

4 '4 

1,022 

3-8 

4*5 

4'0 

2"00 

1*3 

4 

5*8 

1,029 

4-8 

5*8 

5'i 

271 

175 

5 

7*4 

IA37 

5'8 

7'3 

6-3 

335 

2*2 

6 

9-0 

1,045 

6-8 

8-9 

7'6 

4*00 

2-65 

7 

IO"2 

1,052 

7-8 

10-4 

9-0 

4-64 

3*i 

8 

12*0 

1,060 

8-8 

I2'0 

IO#2 

5'29 

3*5 

9 

I3'4 

1,067 

9'8 

13-4 

11 -4 

5'87 

3*9 

10 

1,075 

io-8 

15-0 

127 

6'55 

4*35 

11 

i6*6 

1,083 

ii'9 

i6'5 

14-0 

7*31 

4'8 

12 

l8'2 

1,091 

13-0 

18-1 

15-3 

8-oo 

5*25 

13 

20%0 

I,IOO 
1,108 

14-1 

19-9 

16-8 

8-68 

57 

14 

21  "6 

152 

21*5 

18-0 

9-42 

6-25 

15 

23*2 

I,Il6 

16*2 

23-1 

19-4 

10  06 

6-8 

16 

25 '0 

1,125 

173 

24-8 

20-8 

10-97 

7*3 

17 

26-8 

1,134 

1*5 

26-6 

22*2 

1 1 -84 

7-8 

18 

28*4 

1,142 

19-6 

28-4 

23-6 

12*64 

8-4 

19 

3o*4 

1,152 
1,162 

20 -8 

30-2 

24*9 

l3'SS 

9-0 

20 

32*4 

22'2 

31  *2 

26'3 

H'37 

9'6 

21 

34*2 

1,171 

23*3 

32'0 

27-8 

IO*2 

22 

36ko 

I,l8o 

24*5 

33*o 

29*2 

IO-85 

2.3 

38-0 

1,190 

25*8 

33*9 

307 

1677 

24 

40*0 

1,200 

27*1 

347 

32*I 

17-67 

12*2 

25 

42*0 

I,2IO 

28*4 

357 

33'8 

18*58 

12-9 

26 

44*0 

1,220 

29*6 

36-8 

35*5 

1958 

137 

27 

46*2 

!,23I 

31*0 

37*9 

37*o 

20-59 

14*5 

28 

48*2 

1,241 

32-2 

39  "o 

38-6 

21-42 

15-2 

29 

50-4 

1,252 

33*4 

39'8 

40*2 

22-64 

15*9 

Comparison  of  Hydrometers. 


641 


Table  comparing  Beaume  and  Twaddell  with 
Specific  Gravity  together  with 
Percentage  Table  of  Common  Chemicals. 
Coiitinued. 


PERCENTAGE  OF 


Beaume. 

Twaddell. 

Specific 
Gravity 

Sul- 

[HI  111  1  * 

Spirits 
of 

Nitric 
Acid. 

Caustic 
Soda 

S02  in 
Sodium 
Bisul- 

Acid. 

Salts. 

Na  OH 

phite. 

3° 

52*6 

1,263 

347 

41  *2 

41*5 

23-67 

10  55 

31 

54  5 

I>274 

36'0 

42'4 

43*5 

Z/\  51 

17  5 

32 

57  'o 

t  ?£c 

37*4 

42 '9 

45'° 

•^5  ou 

15  7 

33 

59*4 

1,297 

35  5 

47  1 

20  53 

I96 

34 

01  0 

40*2 

45  O 

27  50 

21  'O 

35 

64*0 

I,320 

41  0 

5°7 

25  53 

22*5 

~>f\ 
j>o 

UO  4 

J>332 

43'° 

52'9 

29*93 

23*0 

37 

69  "O 

T    1A  C 

44*4 

55  u 

31  "22 

23"6^ 

3s 

71  *4 

J>357 

45*5 

57  *3 

32 '47 

39 

74'° 

I>37° 

46*9 

59  0 

33 '69 

40 

/O  O 

i»35j 

4°  j> 

01  7 

34'96 

41 

79*4 

1  >397 

49  d 

64'5 

36*25 

42 

52  0 

1,410 

51  *2 

67'5 

37*47 

43 

04  0 

1,424 

52  5 

70*6 

35  SO 

44 

07  0 

!,435 

54'° 

74*4 

39*99 

45 

90*6 

x,453 

55*4 

75  4 

41  -41 

A& 

40 

93 -6 

1,400 

T  A%? 

56'9 

53  O 

42  03 

47 

90  O 

55  3 

57  I 

A  A 

44  35 

A% 
45 

99  '6 

1,495 

59*6 

92  '6 

46*15 

49 

103-0 

1,514 

6i*o 

96*0 

47  *6o 

50 

106  *o 

1,530 

62*5 

98-0 

49*02 

5i 

109*2 

1,540 

64  0 

IOO'O 

52 

II2'6 

1,563 

65'5 

53 

n6'o 

1,580 

67*0 

54 

119-4 

1,597 

68 -o 

55 

123*0 

1,615 

70*0 

56 

127*0 

1,634 

71*6 

57 

130*0 

1,652 

73*2 

58 

134-0 

1,672 

747 

59 

138-2 

1,691 

76-4 

60 

142-0 

1,711 

78*1 

61 

146-4 

i,732 

79*0 

62 

150*6 

i,753 

817 

63 

i55'o 

i,774 

84-1 

64 

159-0 

1,796 

86-5 

65 

164-0 

1,819 

897 

66 

168-4 

1,840 

96*0 

02 


INDEX. 


A 

Acids,  action  of  on  starch,  43 
Acid,  acetic,  306 
,,     carbolic,  259 
,,     cresylic,  260 
,,        ,,        properties  of,  261 
,,     free  in  fermented  flour,  79  to  82 
,,     free  in  fermented  flour,  action  on 

copper  rollers,  80 
,,     free  in  chloride  zinc,  247 
,,        ,,     China  clay,  148 
,,         ,,     chloride  of  calcium,  227 
, ,        , ,     chloride  of  magnesium,  222 
,,     size,  81,  94,  482 
,,     tallow,  177 
,,        ,,     water,  534,  536 
,,     hydrochloric,  12 
,,        ,,       action  of  on  cotton  fibre, 
[223,  491 

,,     nitric,  12 
,,     salicylic,  256 
,,         ,,        properties  of,  257 
,,     tannic,  on  starch,  43 
Acids,  effect   of  on   orange  chrome 

borders,  530,  576 
Adulteration  of  chloride  of  zinc,  238  et 
,,         ,,     flour,  62,  etseq,  [seq. 
,,         ,,     tallow,  166  etseq. 
Air,  drying  power  of,  in  weaving  sheds, 
587,  etseq. 
,,    oven,  24 

,,    tables   of  moisture  contained  in, 
588  to  602 
Albumen,  vegetable,  53,  65 

,,      estimation  of  in  flour,  65. 
Alizarine  dyes,  565,  et  seq. 
oil,  196 

Alkali,  free,  method  of  testing  for  in 
cloth,  34,  482 
,,     action  on  flour,  41,  81 
,,     action  on  farina,  92  et  seq. 
,,    use  of  in  sizing,  81,  92 

Alumina,  silicate  of,  134 

Ammonia,  12 

Ammonium,  chloride  of,  12 


Ammonium,  chloride  of,  detection  of  in 

chloride  of  zinc,  243 
Ammonium,  oxalate,  12 
,,         sulphide,  12 
Analysis  of  carnallite,  219 
,,       China  clay,  135 
,,       chloride  of  magnesium,  220 
,,       commercial     chloride  of 

.  zinc,  239  to  254 
,,       flour,  71 
Analysis  of  grey  cloth,  481  to  51 1 
soaps,  208,  211 
tallow,  170  to  190 
,,       tallow  substitutes,  191 
Aniline  blues,  305,  569 

,,      black,  "topping "of  dyed  yarns, 

420,  569  et  seq. 
,,         ,,     aged  process  570 

,,     one  bath  process,  570 
Antiseptics  in  fermented  flour,  73  seq. 
,,       method  of  using,  77,  83,  254 
257 

Apparatine,  manufacture  and  use  of, 

125  et  seq. 
Apparatus  for  testing  counts  of  yarn 

and  size  in  cloth,  485 
Apparatus,  chemical,  description  of, 
,,    list  of,  11      [11  to  34 
,,  fat  extraction,  494 

,,  squeezing,  403 

Ash  of  flour,  53 

,,  estimation  of,  61 

Ash  of  Starches,  37,  96,  98 
Aspergillus  Glaucus%  513 
Atmosphere,  effects  of  conditions  of 
on  weaving,  584  et  seq. 
,.       table  of  percentage  of  moist- 
ure in,  588  to  601 
Auramine  Yellow,  305 
Automatic  loom,  457 

B 

Bacteria,  action  of  on  starch,  47,  91 
Back  beams,  method  of  weighting,  356 


ii.  The  Chemistry  and  Practice  of  Sizing. 


Balance  and  Weights,  12  et  seq. 
Ball-bearings,  329 
Ball  sizing,  391 

,,       boil  pipes,  399 

,,       delivery  winch,  406,  435 

„       drying  machine,  406 

flour  becks,  397 
,,       machine,  399 
,,       mixing  becks,  397 
,,       mixings  for  coloured,  412 
,,       operations   involved  in, 

[397  et  seq. 
,,       plant,  397  et  seq, 
,,       size  box,  398 
,,       squeezing  apparatus,  403 
Balling  machine,  409 
Barium  chloride,  12,  164 
Barium  sulphate,  163 
Basic  colours,  305 

,,  test  for  on  alizarine,  56S 

Basin,  evaporating,  29 
Bath,  water,  30 
Beakers,  thin  glass,  28 
Beams,  production  of  soft,  381 

,,      back  method  of  weighting,  356 
,,      crooked,  351 
Becks,  chloride  of  magnesium,  271 
„    flour,  270,  398 
„    mixing,  270,  397 
Bell  wheel  shaft,  342 
Benzo-chrome  brown,  305 

,,    sky  blue,  305 
Bevel  wheels,  384 
Bismarck  brown,  305 
Black  mildew,  513 

Bleaching,  Caustic  Soda  process  of,  560 
Bleached  cloth,  damages  caused  to  in 

coloured  borders,  564  et  seq. 
Bleached  palm  oil,  196 
Bleached  warps,  the  blueing  of,  417 
Bleached  yarns,  imitation,  417 
Bleaching,  cotton  cloth,  545  to  583 

,,       effect  of  excessive  sizing  on,- 

301  et  seq. 
„       goods  with  coloured  borders, 

564  et  seq. 
,,       hank,  process  of,  449  et  seq. 
,,       Open  Process  of,  562 
,,       operations  involved  in,  546, 
et  seq. 

„  „        bowking,  552 

,,  ,,        chemicking,  557 

„  ,,       liming,  551 

,,       singeing,  549 
,,  ,,       souring,  554 

„  ,,        soda  ash  boil,  557 


Bleaching  operations,  stamping  and 
stitching,  548 
„  „        steeping,  550 

„  „        washing,  550 

,,       plain  goods,  precautions  to 

be  observed  during,  563 
,,       pure  white,  558 
„       scouring  Process  of,  561 
„       storage  of  cloth  previous  to, 
„       warps,  422  [547 
Blue  aniline,  305 
,,    colours  used  for  tinting  size,  305, 
,,    indigo,  310,  420,  569      [420,  421 
,,    ultramarine,  308 
Blueing  bleached  warps,  417 
Boiling  pan,  for  size,  374  to  377 
Boiling  and  washing  machine,  432 
Boil  pipes,  318,  399,  434 
Boil  taps,  358 
Bone  fat,  193 

,,      in  tallow,  175 
Bottles,  specific  gravity,  26 
,,      reagent,  22 

wash,  26 
,,      weighing,  22 
Bowkimj,  552 
Bran  in  flour,  54 
Brick-red  mildew,  515 
British  gum,  123 

,,        preparation  of,  123 
British  gum,  properties  of,  124 

,,         tests  for,  53 
Broken  bottoms,  364 
Brushing  machine  (hank  sizing),  445 


c 

Calcium,  chloride  of,  226 
,,       carbonate  of,  499 

,,       oxalate  of,  12 
oxide  of,  499 
Carbolic  acid,  259 
Carnallite,  219 
Castor  oil,  196,  205 
Caustic  soda,  process  of  bleaching,  560 
Cellulose,  in  flour,  52 

,,       in  starch,  37  et  seq. 

,,       test  for  in  cotton,  465  et  seq. 
Change  wheels,  driving,  334 
Chemical  apparatus,  description  of,  11  to 
list  of,  11  [34 

,,      balance,  12  et  seq. 
Chemicking,  557 
Chilian  flour,  71 
China  clay,  134  et 


Index. 


iii. 


China  clay,  analyses  of,  135 

boiling  of,  150  et  seq, 
,,       colour  of,  145 
,,       composition  of,  134 

feel  of,  144 
,,       grit,  presence  of  in,  143 
,,       method  of  mixing,  150,  288 
,,       mining  of,  134  et  seq. 

pan,  271 
,,        powdered,  151 
,,       quality  of,  142  et  seq. 
,,       spurting  of,  215 

'standard'  for  size  mixings, 
150 

,,        treatment  of  in  preparing 

size,  150,  28S 
,,       value  of  powdered,  151 
Chloramine  yellow,  305  [et  seq. 

Chloride  of  ammonium,  detection  of 

in  chloride  of  zinc,  244 
Chloride  of  barium,  12,  164 
,,     calcium,  226 
,,        ,,       acid  in,  227 
,,        ,,       detection     of  in 
chloride  of  zinc,  242 
Chloide  of  calcium,  impurities  in,  227 
,,      preparation  of,  227 
,,  ,,      properties  of,  227 

,,  ,,      iron  in,  228 

,,  ,,      hypochlorite  of  cal- 

cium in,  228 
Chloride  of  iron  in  chloride  of  zinc,  245 
Chloride  of  magnesium.  218  et  seq. 
,,  action  of  on  soap,  215 
,,  action  of  on  starch,  43 
,,  analyses  of,  218  et  seq. 
.,     composition  of,  220 

effect  of  heat  on,  222,  223, 
550,  581 
,,     effect  on  weaving,  217  et  seq. 

impurities  in,  220  et  seq. 
,,     in  chloride  of  zinc,  243 

in  Epsom  salts,  224  et  seq. 
,,     iron  stains  due  to  exces- 
sive use  of,  224,  535,  536 
et  seq. 

,,     mildew  due   to  excessive 

use  of,  519  et  seq. 
,,     preparation  of,  219 
,,     sulphates  in,  220 
,,     tests  for  impurities  in,  220 

Chloride  of  sodium,  221  [et  seq. 

Chloride  of  zinc,  235 

,,  adulteration  of,  238 

,,  analyses   of  different 

samples  of,  253 


Chloride  of  zinc,  common  salt  in,  240 
,,  detection  of  chloride  of 

ammonium  in,  244 
,,  detectionof  chloride  of 

calcium  in,  242 
,,  free  acid  in,  247 

,,  iron  salts  in,  245 

,,  magnesium  in,  243 

,,  manufacture  of,  235 

,,  purification  of,  236 

Chrysoidine  Orange  Dye,  305 

Chrome,  orange  borders,  530,  575 

Clay  pan,  271 

Classification  of  oils,  fats,  and  waxes, 
Cloth,  analysis  of,  481  et  seq.  [205 
,,     analysis  of  mildewed,  511 
,,     conditions  favourable  to  mildew 

in,  512,  et  seq. 
,,     bleaching  of,  545,  et  seq. 
,,     ''feel"  on,  285,  287 

free  acid  in,  482 
,,     free  alkali  in,  482 
Cloth,  grey,  analysis  of,  481  et  seq. 
,,     microscopic  examination  of,  515 
,,     moisture  in,  determination  of, 
,,     packing  of,  543  [492 
,,     quadrant,  Lancaster,  485 
,,     qualitative  analysis  of,  482  et  seq. 
,,     quantitative  analysis  of,  490  et 

seq. 

tests  applied  to  for  chlorides  in, 
482,  505  et  seq. 
Cloth,  test  for  China  clay  in,  484,  495 
,,  ,,     dextrin  in,  484 

,,     test  for  magnesium  salts  in,  483, 
497 

,,  ,,    starchy  matters  in,  484, 

510 

,,  ,,    sulphates  in,  482,  503 

Coal  tar  colours,  305 
Cocoa-nut  oil,  195 

Cold  air,  effect  on  weaving,  585,  592 
et  seq. 

Coloured  back  beam,  388 
box,  382 

,,       borders,  damage  to,  in  bleach- 
ing, 564  et  seq. 
,,       tapeing,  382  et  seq. 
,,  ,,     arrangement  for  drying 

of,  386 

,,       yarn,  sizing  of,  382  et  seq. 
,,  ,,     mildew  on,  385 

Colours  used  for  size  tinting,  305,  416 
et  seq. 

,,      method  of  mixing,  306,  307 
Combs,  doffing  insertion  of,  363 


iv.  The  Chemistry  and  Practice  of  Sizing. 


Combs,  striking,  359 
Common  Salt,  detection  of  in  chloride 
of  magnesium,  221 
,,         detection  of  in  chloride 
of  zinc,  240 
Cone  drums,  driving  331 
Cone  drum  straps,  332 
Congo  Red,  34 
Conidia,  513 

Copper  roller  in  tape  frame,  322 

,,         action  of  acids  on,  79 
,,         expansion  joint  in,  322 
,,         mid-feathers  in,  322 
,,         on  washing  machine,  433 
Cotton,  463  et  seq. 

,,      adapted  for  "heavy"  sizing, 
266,  465 

,,      adapted  for  use  in  automatic 

loom,  457 
,,      American,  463 
,,      Barbadoes,  463 
,,      chemical  composition  of,  465 
,,      detection  of  in  mixed  fabrics, 
476 

,,      excess  moisture  in,  469  et  seq, 
,,      fat,  determination  of  in  cloth, 
493 

,,      fatty    matters    contained  in, 
468 

,,      hair's  diameter  of,  465 

,,      hair's  length  of,  465 

,,      hairy,  463 

,,      herbaceous,  463 

,,      length  of  staple,  465 

,,      microscopic  examination  of,  473 

,,      mineral  matter  in,  467 

,,  ,,  analysis  of,  467 

,,      moisture  in,  469  et  seq. 

,,      over-damping  of,  469 

,,      plants,  varieties  of,  463 

,,      seed  oil,  181 

,,  wax  and  oil  contained  in,  468 
Corn  starch,  104 

Counts  of  yarn,  determination  of  in 

cloth,  486  et  seq. 
Creel  for  back-beam,  315 
Cresylic  acid,  260 
Crucible  porcelain,  33 

,,     platinum,  33 
Cylinders,  drying  (ball  sizing),  406 

,,       of  tape  frame,  width  of,  327 

D 

Damaged  goods,  examination  of,  525 
,,  cause  of,  512  et  seq. 


Deliquescent  salts,  217  et  seq. 

,,       effect  of  in  producing 
mildew,  471,  ^Y]  et  seq. 
,,        effect  of  in  producing 
iron-stains,  534  et  seq. 
„       used  for  damping  yarn, 
Delivery  Winch,  399,  435  [470 
Density  of  liquids,  determination  of, 

26,  27 
Desiccator,  29 

Dextrin,  123,  see  Appendix  A 

,,      in  flour,  53 

,,      preparation  of,  123 

,,      test  for  in  cloth,  484 
Dhootie  marker,  342 

,,    borders,  bleaching  of,  564  et  seq. 

,,        „       mildew  on,  385 
Diamine  sky  blue,  305 
Dickinson's  tape  frame  (see  plate  xii. ) 
Direct  dyes,  used  in  tinting.  305 
Doffing  Combs,  insertion  of,  363 
Double-acting  buckets,  329 
Drying  cylinders,  327,  406 

,,  for  coloured  yarns,  388 

Machine,  406 

, ,     power  of  air  for,  587  et  seq. 

, ,     stoves,  447  et  seq. 

,,     warps  in  tape  sizing,  364,  385 

[et  seq. 

,,     in  ball  sizing,  393,  406 
Draw  roller,  340 
Driving  motion,  331  et  seq. 

,,  change  wheel,  334 

,,  cone  drums,  331 

Dyeing,  Native,  for  Sizing,  299 

, ,        "  Sliver, "  see  appendix  B 
Dyes,  list  of,  used  for  tinting,  305,  417 
, ,  used  for  "topping,"  420,  567  et  seq. 

E 

Egyptian,  tinting  of  cotton,  for  shade  of, 
[311  et  seq. 

,,       wheaten  flour,  71 
English  wheaten  flour,  71 
Ejector  for  chloride  of  magnesium,  271 
Epsom  Salts,  composition  of,  154 

,,      chloride  of  magnesium  in,  154 
,,      damage  produced  in  cloth  by 
chloride  of  magnesium  in, 
154  et  seq. 
,,      impurities  in,  160 

tests  for  impurities  in,  160 
Expansion  joint,  322 
Equilibrium  valve,  353 
Eyelets,  399 


Index, 


v. 


Falling  roller,  326 
Fans,  in  tape  frame,  349 

,,    ventilating,  603  et  seq. 
Farina,  87 

,,  action  of  caustic  soda  in  prevent- 
ing loss  of  strength  in  size 
made  from,  92 

,,    microscopic  appearance  of,  50 

,,    preparation  of,  88 

,,  quality  of,  test  for  95 
Fats,  melting  point  of,  174 

,,    vaporising  point  of,  170 
Fats,  oils  and  waxes,  165  et  seq. 
Fatty  matters  in  cloth,  estimation  of.  493 
Feed  pipe,  318 

Fermentation,  action  of  on  gluten,  73  et 
,,  of  flour,  73  [seq, 

, ,  of  flour,  effect  of,  73  et  seq. 

Fermented  flour,  free  acid  in,  79 
Filtering  funnels,  25 
,,       operation  of,  25 
,,       paper,  25 
"  Finishing,"  effect  of  sizing  on,  301 
Finishing  roller,  323 

,,  copper  sleeve  on,  325 

flannels,  323 

Flax,  473 

,,     microscopic  appearance  of,  473 
Flasks,  glass,  287 
Flash  point  of  Tallow,  173 
Float  roller  for  sow  box,  320 
Flour,  adulteration  of,  61  et  seq. 

,,      with  other  starches,  63 
albumen  of,  53 

amount  of  water  required  for 

mixing,  277 
amount  of  chloride  of  zinc  re- 
quired, 254,  277,  518 
analysis  of,  64  et  seq. 
ash  of,  64 

becks,  269,  277,  397 
cellulose  of,  52 
Chilian,  71 
colour  of,  54  et  seq. 
,,  method  of  testing, 

54  et  seq. 
composition  of,  52  et  seq. 
detection  of  mineral  matters  in, 
61  et  seq. 
,,       of  starches,  63 
dextrin  in,  53,  65 
Egyptian,  71 
English,  71 

estimation  of  albumen  in,  65 
,,      ash  in,  62 


Flour,  estimation  of  gluten  in,  52,  58 
,,  ,,       moisture  in,  57 

starch  of,  49, 53,  63 
,,  sugar  in,  53,  65 

fermentation  of,  71  et  seq. 
gluten  in,  52,  58 
,,      maize,  101 
,,      milling,  see  appendix  A 
,,      moisture  in,  54,  57 
,,      pastes,  consistency  of,  55 
Flour,  rice,  properties  and  uses  of,  108 
,,      separation  of  starch  from,  74, 
102,  109 

,,     time  required  for  mixing,  280 
,,      treatment  of,  72,  277  et  seq. 
,,      Twaddelling  of,  278,  280 
,,      use  of  in  sizing,  85  et  seq. 
,,      wheaten,  52  et  seq. 
Free  acid  in  chloride  of  zinc,  247 
,,      in  fermented  flour,  79,  82 
,,      in  tallow,  177 
,,      mode  of  detecting,  34 
Friction  bowls,  337 
lever,  337 
,,       motion,  336  et  seq. 
,,       plates,  337 
Fungi,  512 
Fungus,  black,  513 
,,      brick-red,  515 
,,      green,  513 
,,      on  cloth,  detection  of  and 

tests  for,  516 
,,      pink,  514 

purple,  514 
,,      yellow,  513 
Funnels,  25 

,,       separating,  29 


Gear,  Throw-out,  434 
Geranine  pink,  305 
Glasses,  test,  27 

„      watch  and  clip,  22 
Glauber's  salts,  161 
Glucose,  65,  133,  233 
Gluten,  52,  58,  101,  107 

,,      action  of  caustic  soda  on,  101, 
107 

action  of  chloride  of  zinc  on,  84 
estimation  of  in  flour,  58 
properties  of,  60 
quality  of,  59 
Glycerin,  229 

,,         impurities  in  and  adultera- 
tion of,  230 


vi.  The  Chemistry  and  Practice  of  Sizing. 


Glycerin,  preparation  of,  229 

,,         properties  of,  230 
Glycerin  substitutes,  232 
Gossypium  bat  badetise,  463 
,,       herbaceuni)  463 
,,       hirs ut urn,  463 
,,       religiosum,  463 
Green  Mildew,  513 

,,       development  of,  513 
Guide  rollers,  386 
Gum  dragon,  127 
,,  tragacanth,  127 
,,    tragasol,  129 
Gypsum,  162 

H 

Hank  Bleaching,  process  of,  449 
Hank  sizing,  436  et  seq. 

,,         brushing  machine,  445 

[et  seq. 

,,  drying,  447 

,,  stoves,  447  et  seq. 

,,         machine,  438 

,,  method  of  applying  the  size 

440  et  seq. 
,,  method  of  mixing  size,  442 

,,         plant,  description  of,  438 
et  seq. 

Hanks,  hydro-extracting  of,  451 
"Headings,"  damage  caused  to,  564, 

et  seq. 

Headstock  of  tape  frame,  315,  331  et  seq. 
"Heavy"  sizing,  5,  266,  288,  366,  401 

,,       size  mixings,  298 
Hemp,  473 

Humidifier,  Howorth's  see  plate  xxi., 
p,  610 

,,        Matthews  &  Yates',  see  plate 

Humidifying  the  air  of  weaving  sheds, 
609  et  seq. 

Humidity    table   shewing  percentage 

of,  588  to  602 
Hydrochloric  acid,  12 

,,     action  of  on  cotton  fibre, 
223,  466,  491,  554 
Hydro-extractor,  451 
Hydrometer,  Twaddell's  27 

,,  use  of  for  flour,  278,  280 
,,    use  of  for  chloride  of 

magnesium,  283 
,,    use  of  for  chloride  of 

zinc,  284 
,,    use  of  for  size  mixings, 
285,  286 


I 

Imitation  bleached  warps,  417 
Immersion  rollers,  320,  399,  433 
skeleton,  321 
doffing  combs  of,  303 
Indian  Corn  starch,  101 

,,  microscopic  appearance 

of  granules,  50 

Indicators,  34 

Congo  Red,  34 
,,       Litmus,  34 

Methyl  Orange,  34 

Indigo,  310 

,,     Indigo  topping  of,  420,  569 
Ingredients  necessary  for  making  size, 
8,  9 

,,       containing  excess  of  water, 

275  et  seq. 
,,       method   of  preparing,  for 
size,  273  et  seq. 
Iodine,  solution  of,  12 
Irish  Moss,  132 

Iron,  chloride  of  in  chloride  of  zinc, 
245,  540 

,,  logwood  test  for,  246 

Iron-stains,  533 

,,         classification  of,  534 

,,         development  of,  534  et  seq. 

,,         origin  of,  534 

,,         removal  of  from  cloth,  542 

,,         test  for,  541  et  seq. 

Iron-stained  selvedges,  cause  of,  347 

Irregular  mixings,  cause  of,  285  et  seq. 

Japan  wax,  204,  205 

K 

Kaolin,  134 
Kieserite,  154 
Kier,  427 

,,    boiling  in  warp  bleaching,  423 


L 

"  Lappers,"  325 
"  Laying  in,"  361 
Lease  bands,  359  et  seq. 

,,    rods,  352,  361  ■ 
Let-off  papers,  434 
Li^ht  weights  in  sizing,  358,  380 
Lime,  sulphate  of,  162 
Liming,  551 
Linen  fibre,  473 

,,     separation  of  from  cotton  in 
mixed  fabric,  479 


Index. 


vii. 


Linen,  imitation  of  in  tinting  cotton,  421 
Litmus  paper,  34 
Logwood  test  for  iron,  246 
Loom,  automatic,  457 
,,     speed  of,  457 

M 

Magnesium,  chloride  of,  21 S  ct  seq. 
,,  ,,      analysis  of,  210 

[ct  scq. 

Magnesium,  chloride  of,  as  impurity  in 
Epsom  salts,  224 

,,  ,,      beck,  271   [ct  scq. 

,,  ,,      bleaching,  effect 

225,  581 

,,  ,,      damage,  produced 

by,  1 55  et  scq. 

,,  ,,      effects  of  heat  on, 

222,  223,  550,  581 

,,  ,,      method  of  meas- 

uring, 283 

,,  ,,      strength  of,  282 

,,  ,,      tests  for  impurities 

in,  220  et  seq. 

,,  ,,      Twaddelling  of. 

283 

,,         sulphate  of,  154 
Maize  flour,  101 

,,         ,,    mildew  due  to  use  of,  105 
,,     starch,  101 
,,  granules,  50 

,,  properties  of  in  sizing,  101  et  seq. 
Marking  or  measuring  motion,  342 

ct  scq. 
Marrow  fat,  193 

,,        in  tallow,  175 
"  Medium"  sizing,  265 
Melting  point,  of  fats,  174,  205 
Methylene  blue,  305 
Methyl  orange  indicator,  34 

,,     violet,  305 
Mica,  140 

Microscope,  description  of,  20 
Mid-feather,  in  sow  box,  326 
Mildew,  512  et  scq. 

,,    action  of  deliquescent  salts  in 

producing,  224  471,  519 
, ,    action  of  moisture  in  producing, 
522 

,,    black,  513 

,,       ,,    origin  of  in  cloth,  513 
,,    brick -red,  513 
,,    green,  513 

,,    microscopic  examination  ol 
cloth  for,  515 


Mildew,  pink,  514 

,,     prevention  of  by  fermenting 
flour,  73 

,,  produced  by  use  of  maize  flour, 
,,  purple,  514  [105 
,,    salicylic  acid  use  of  for 

preventing,  77,  257,  533 
,,    various  causes  of,  513  ct  seq. 
,,    yellow,  513 
,,    zinc  chloride,  use  of,  for 

preventing,  84,  254,  518 
Mildewed  cloth,  analyses  of,  521  et  seq. 
Mikado  orange  dye,  305 
Mineral  matters,  estimation  of  in  cloth, 
495 

,,  in  flour,  53 

n  estimation  of,62 

5  j  chloroform  test 

for,  63 

Mixings,  for  heavy  sizing,  298 
,,      for  coloured  yarn,  412 
,,      for  light  sizing,  297,  413 
,,      for  medium  sizing,  297 
,,      method  of  making,  284  ct  scq. 

Moisture  determination  of,  in  cloth,  492 
,,      excess  of  in  yarns,  469  et  seq. 
>>  sizing  ingredients, 275 

,,      its  effect  on  yarns  for  weaving, 
584  et  seq. 
in  China  clay,  135,  144,  509 
,,     in  flour,  57,  64 
,,      production  of  mildew  by 

excess  of,  471 ,  517  et  seq. 

Moss,  Irish,  132 

Mule  yarn,  458 

,,         for  heavy  sizing,  266,  461 

Muriatic  acid,  12 

N 

Native  dyeing,  size  suitable  for,  299 
Neutralisation  of  acid  in  fermented 

flour,  81 
Nitrate  of  silver,  12 
Nitric  acid,  12 

o 

Oil  alizarine,  196 
,,  black,  542,  583 
,,    castor,  196,  205 
,,   cotton,  seed  in  tallow,  181 
,,   cocoa-nut,  195 

,,    hydrocarbon  or  mineral  in  tallow, 

167,  172 
,,   oleine,  196 
,,   olive,  195 


viii.  The  Chemistry  and  Practice  oj  Sizing. 


Oil,  palm,  196 

mineral,  stains,  543,  580 
,,   soluble,  198 
.,   Turkey  red,  196 
Oils  and  fats,  examination  of,  165  etseq. 
Oil  and  wax  in  cotton,  468 
Orange  chrome  dyes  on  coloured  bor- 
dered goods,  572,  576 
et  seq, 

,,  damage  to  in  bleaching, 

576  et  seq. 

,,      chrysoidine,  305 
Orange,  Mikado,  305 

,,      Turkey,  565  et  scq. 
Open  process  of  bleaching,  562 
Oryza,  saliva,  108 

Oxford  shirtings  cause  of  injury  to,  155 
,,  ,,      explanation  of,  158 

Oven,  air,  24 

,,     steam,  24 
Over-dried,  yarn,  364 
Over-flow  pipes,  434 

p 

Packing,  for  grey  cloth,  543 

Palm  oil,  196 

Pan,  boiling,  374  et  seq. 

„    clay,  271 
Paper  filtering,  25 
,,     litmus,  34 
,,     used  in  packing,  543 
Paraffin  wax,  202 

,,      use  of  in  sizing,  203 

,,      objection  to  for  goods,  to  be 

bleached,  203 
,,      stains,  580 
Pastes,  farina,  method  of  testing, 
strength,  of,  95 
,,    flour,  method  of  testing 

strength  of,  55,  et  seq. 
Penicillium  glaucum,  513 
Pink  mildew,  514 

Pipes  for  conveying  size,  arrangement 
of,  269  et  seg. 
,,    boil,  318,  373,  400,  434 
let  off,  434 
Plant,  ball  sizing,  397 
Porcelain  basin,  29 

,,      crucible  33 
Potato,  analysis  of,  88 
Potato  starch,  87 

,,      action  of  caustic  soda  in  pre- 
venting loss  of  strength,  92 
,,      microscopical  appearance  of, 
50 


Potato  starch,  paste  produced  by,  95 

,,      preparation  and  properties  of, 
87,  et  seq. 
Press,  roller,  345  et  seq. 
Press,  one  roller,  345 

,,     friction  motion  for,  345 

,,     lever,  345 

,,     two  roller,  347 
Pressing  motion,  344 
Preparation  of  yarn  for  weaving,  455 
Pump,  for  size,  368  [et  seq. 

,,      overflow  valve  of,  369 
Pure  size,  263,  287,  296 
Purple  mildew,  514 

Q 

Qualitative  analysis  of  cloth,  481  et  seq. 
Quantitative  analysis  of  cloth,  490  et  seq. 

R 

Ratchet  wheel,  350 

Reagents,  list  of,  12 

Reagent  bottles,  22 

Red  mildew,  515 

Reducing  valve,  353 

Reed,  action  of  acid  size  on,  534 

,,     action  of  chloride  ot  magnesium 
on,  535 

, ,     action  of  grit  in  China  clay  on,  143 
,,     action  of  maize  flour  on,  224 
,,    action  of  sago  flour  on,  100 
Regulating  screws,  368 

clutch,  372 
Retort  stand,  33 
Rice  flour,  108 

,,       analyses  of,  109 
Rice  starch,  1 10 

,,       granules,  appearance  of,  51 
preparation  of,  109 
Ring  yarn,  458 
Roller,  copper,  322,  399,  446 
draw,  340 
,,     guide,  386 
,,     immersion,  320,  399,  433 
„     felling,  320 
,,     finishing,  323 
,,     flannels,  323,  403 
„     float,  320 
, ,     presses,  345  et  seq. 
Rollers,  sheeting,  351 
Rollers,  squeezing,  403 

,,  lapping  of,  403 


Index. 


ix. 


S 

Sago,  97 

,,    microscopic,  appearance  of  gran- 
ules, 51 

Sago,  use  of  in  sizing,  99  et  seq. 
Salicylic  acid,  256 

,,       use  of  in  pure  sizing,  77,  257 
Scouring  process,  in  bleaching,  56  L 
Separation  of  cotton  and  linen,  479 
silk,  480 
,,      wool,  476 
Silicate  of  alumina,  134 

,,      magnesia,  164 

,,      soda,  164 
Silver  nitrate,  12 
Singeing,  549 

Size,  boiling  apparatus,  374,  et  seq. 

,,    boiling  of,  290,  372  et  seq. 

,,   box,  316,  398,  439 

,,   estimation  of  in  cloth,  485,  491 

„   heavy,  5,  266,  288,  366,  401 

,,   light,  5,  287,  358,  380 

,,   method  of  mixing,  284^/  seq. 

,,    mixing  rooms,  269 

,,    mixings,  296  et  seq. 

,,         ,,       strength  of,  279,  et  seq. 

,,         ,,       regularity  of,  367  et  seq. 

,,         ,,       preparation  of,273^/  seq. 

,,         ,,       tendering  caused  by, 301 

,,    mode  of  applying,  see  tape,  warp 
and  hank  sizing. 

,,   pure,  263,  287,  296 
Sized  grey  cloth,  analysis  of,  481  et  seq. 
Sizing,  classification  of,  262 

,,      ball  or  warp,  391  et  seq. 

,,      cotton,  best  adapted  for,  266,465 

,,      effect  of,  on  finishing,  301 

,,      for  native  dyeing,  299 

,,     hank,  436  et  seq. 

,,     heavy,  5,  266,  288,  366,  401 

,,     light,  358,  380 

.,      list  of  substances  used  in,  8,  9 

,,      machine  ball  {plate  xiv.), 

,,  ,,       hank,  441 

,,  ,,       tape  {plate  xii.) 

,,      medium,  265 

,,     practical  tape,  354:  et  seq. 
pure,  263,  287,  296 

,,      tape,  354 

,,      uniformity  in,  367  et  seq. 
" Sliver"  dyeing,  new  process  of,  see 

appendix  B 
Soap,  206 

,,    analysis  of,  211 

,,    composition  of,  206 


Soap,  estimation  of  fatty  acids  in,  212 
Soap,  hard,  207,  et  seq. 

,,         analyses  of  various,  208 
,,         manufacture  of,  207 
,,         propeities  of,  214 
,,         resin  use  of  in  bleaching, 
Soap,  soft,  209  [557 
analyses  of  various,  211 
,,       preparation  of,  209 
quality  of,  209 
Soap,  use  of  in  sizing,  214 

stone,  164 
Soda,  caustic  action  on  starch,  41 

,,  action  on  farina  in  preventing 
loss  of  strength,  41,  92 
,,       process  of  bleaching,  560 
Sodium  phosphate,  12 
Soft  beams,  97,  381 
Soft  places  in  hank  sizing,  443 
Softeners,  1 65,  et  seq. 
Solatium  tuberosum,  87 
Soluble  starch,  100  et  seq. 

,,       ,,    American  process  of 
manufacture,  121  et  seq, 
,,       ,,    German  process  of  manu- 
facture, 113 
,,       ,,    use  of  in  sizing,  120 
,,    oil,  198 
Souring,  424,  431,  450,  554 
"Sow"-box,  316^  seq. 

boil  pipes  of,  318,  373 
,.       copper  roller  of,  322 
falling  roller  of,  326 
,,       feed  pipe  of,  318 
,,       finishing  roller  of,  323 

float  roller  of,  320 
,,        immersion  roller  of,  320 
mid-feather  of,  326 
Specific  gravity  of  liquids,  26,  278,  282 

,.  size  mixtures,  285 

Spermaceti,  201 
Spores  mildew,  515 

,,         detection  of  by  means 
of  microscope,  515 

Spur  wheels,  384 
Squeezing  apparatus,  403 
Stains,  black  oil,  542,  583 

,,      iron  on  cloth,  533  et  seq. 

,,      mildew  on  cloth,  512  et  seq. 

,,      mineral  oil,  543,  580  et  seq. 

,,      parraffin  wax,  580 
Stamping,  548 
Stand,  funnel,  25 

,,      retort,  33 

,,      tripod,  33 


x.  The  Chemistry  and  Practice  of  Sizing. 


Starch,  35  et  seq. 

,,      action  of  acid  on,  43 
.,  ,,       alkalies  on,  41 

,,       bacteria  on,  47 
,,  ,,       borax  on,  44 

diastase  on,  47 
,,  ,,       heat  on,  40 

,,  ,,       mineral  salts  on,  43 

,,      cellulose,  37 
,,      chemical  composition  of,  37 
,,      detection  of,  37,  48 

estimation  of,  66 
,,      granules,  microscopic  appear- 
ance of,  49  et  seq. 
Starch,  granulose,  37 

,,      effect  of  boiling,  290 

maize  or  Indian  corn,  101 
Starch,  potato,  87 
rice,  110 
,,       sago,  97 
,,       soluble,  110  et  seq. 
,,       structure  of,  37 
tapioca,  107 
Starch,  test  for,  36 

,,      wheaten,  49,  79 
Starches,  determination  of  in  flour,  66 
,,  ,,    mixtures, 49 

,,       detection  of  in  cloth,  484 
,,       microscopical  appearance  of 
{see  plate  i. ), 
Steaming  in  weaving  sheds,  584  et  seq. 
Steam  trap,  330 

,,  bath  or  oven,  24 
Stearine,  181,  199,  200 
Steatite,  164 

''Steeping"  with  zinc.  82  et  seq. 
,,         in  bleaching,  553 
,,         previous  to  bleaching,  550 
Stitching,  548 
Straps,  slipping  of,  331 
"Striking"  comb,  359 
"Striking,"  360 
"Stuffing"  boxes,  330 
Substances  used  in  sizing,  list  of,  8 
Substantive  colours,  305 
Sulphates,  test  for,  220,  243,  482,  503 
Sulphate  of  barium,  properties,  of,  163 

,,       lime,  properties  of,  162 

,,       magnesia,  154 

,,       soda,  161 

T 

Tallow,  adulteration  of  with  bone  fat, 
175  et  seq. 
,,  with  cotton  seed  oil,  181 


Tallow,  adulteration  of  with  chloride  of 
magnesium,  178 

, ,  with  mineral  oil  and  wax 

172,  182 

,,  with  mineral  substances, 

179 

„  with  starch,  176  et  seq. 

with  water,  172,  179 
Tallow,  analysis  of,  176  et  seq. 
,,      adulteration  of,  166 
,,      composition  of  165 
,,      examinations  of,  170  et  seq. 
,,      fatty  acids  in,  177,  181,  186 
,,      free  acids  in,  177 
,,      flash  point  of,  173 
,,      melting  point  of,  174 

mineral  oil  in,  170,  172,  174, 
181,  182,  179 
,,      minerals  in,  179 
,,      rancidity  of,  177 
,,      saponification  equivalentof,  188 
,,      specific  gravity  of,  189 
,,      starch  in,  177 
,,      substitutes,  190 
,,      tests  for,  170  et  seq. 
,,      vaporising  point  of,  170 

water  in,  test  for,  170,  172,  179 
,,      Yorkshire  grease  in,  170,  180 
Tap,  sieve,  368 
Tapers,  354 

Tape  frame,  Wm.  Dickinson  &  Sons, 
(plate  xii.) 
creel,  315 
cylinders,  327 
,,       draw  roller,  340 
,,       driving  motion,  331 
,.       friction  motion,  336  et  seq. 
,,       general  description  of,  315 

et  seq. 

,,       headstock  and  its  appliances 
and  motions,  331  et  seq. 

,.       lease  rods,  352 

. ,        marking  motion,  342  et  seq. 

,,       pressing  motion,  344 

,,       slow  motion,  334 

,,       valve  reducing,  353 

,,       wraith  of,  349 
Tape  frame,  Sow-box,  316  et  seq. 
Tape  Sizing,  practice  of,  354  et  seq. 

, ,    broken  bottoms,  cause  of  in,  364 

,,    changing  wheels,  of  a  set  in,  356 
356 

,,    coloured,  382 
,,    drying  of  yarn  in,  376,  385 
,,    finish  on  the  yarn  in,  381 
,,    heavy,  366 


Index. 


xi. 


Tape  Sizing,  light,  365 

,,    uniform  boiling  in,  372 
drying,  376 

feed  of  size,  368 

Tapioca,  107 

,,      microscopic    appearance  cf 
granules,  51 
Test  glasses,  27 

,,  tubes,  22 
Testing  of  sized  yarn,  459  et  seq. 
Thermometer,  30 
Thymol,  258 

,,       preparation,  258 
Thymol,  test  for,  258 
Tincture  of  logwood,  246 
Tinting  linen  shades  on  cotton,  421 
Tinting  of  size,  304  et  seq. 

,,  colours  used  for  305 

Egyptian  shade,  311 
Tinting  of  warps  in  ball  sizing,  416  to 
422 

Tongs,  crucible,  32 
"Topping,"  420,  567,  568 
Turkey  chocolate,  565 

, ,     orange  dye,  565 

,,     purple,  565 

,,     red,  565 

,,     yellow,  565 
Triangles,  32 

Twaddell's  hydrometer,  use  of,  27 
Twirling,  384 

,,       prevention  of,  389 
Twist,  mule,  266,  457 

,,     ring,  457 


u 

Ultramarine,  308 
Uniform  "feel,"  367 
,,      boiling,  372 
,,      drying,  376 
,,     feed  of  size,  368 
„     sizing,  367 
,,      weight,  366 


v 

Valve,  equilibrium,  353 

,,    overflow,  369 

,,    safety,  353 

,,    self-feed,  371 

,,    reducing,  353 
Vaporising  point  of  tallow,  170 
Ventilation  in  weaving  sheds,  584  et  %e%  ! ; 


Ventilation  by  extraction,  603  et  seq. 
,,         by  plenum  principle,  607 
,,         Gregson's,  608         [et  seq. 

Howorth's,  608 
,,         Matthews  &  Yates',  608 
,,         Union  Engineering,  Co.  606 

w 

Warp,  drying  of,  393,  447 
,,     over  drying  of,  364,  393 
, ,     sizing  {see  ball  sizing)  391  et  seq. 

Warpers  and  their  duties,  456 

Warps,  tinting  of  in  ball  sizing,  415 

Wash  bottle,  26 

Washing,  in  bleaching,  424,  431,  550 
Watch  glasses  and  clip,  use  of.  23 
Water  bath,  30 
Water  in  cotton,  469  et  seq. 

,,     in  tallow,  172,  179 
Wax,  of  cotton,  468 

,,    Japan,  204,  205 

,,    paraffin,  202 

,,     spermacetti,  201 
Weaving,  effects  of  dry  winds  on,  584 
et  seq. 

,,       effects  of  moisture  on,  584 
et  seq. 

Weaving,  effect  of  tapeing  on,  455 

, ,       effect  of  winding  and  warping 
on,  455 

,,       use  of  automatic  loom,  457 
,,       use  of  ring  and  mule  yarn,  458 
Weaving  sheds,  humidifying  of,  and 

ventilation  of,  584  et  seq. 
Weighing,  operation  of,  17  et  seq. 

bottle,  22 
Wheaten  flour,  52  et  seq. 

,,  determination  of  value  of 

for  sizing,  54  et  seq. 
,,  use  of  in  sizing,  85 

Winch,  delivery,  399,  435 
Wool,  474 

,,    and  cotton,  analysis  of  mixture 
of,  476 

,,    and  silk,  analysis  of  mixture  of, 
480 

Wraith,  349 

,,     for  dhootie  borders,  390 
Wringing  machine,  hank  sizing,  439 

Y 

Yarns,    coloured,    sizing    of,  vide 
coloured   tapeing,    ball  and 
hanli  sizing.'  |  I  ',',''','/,>'/> 


xii. 


The  Chemistry  and  Practice  of  Sizing. 


Yarns,  counts  of,  from  cloth,  486  et  seq. 
deliquescent  chemicals,  use  of  to 
increase  the  moisture,  469  et  seq. 
,,      elasticity  of,  459  et  seq. 
,,      for  heavy  sizing,  266 
,,      good  finish  on,  381 
,,     over-dried,  method  of  rectifying, 
364 

,,      preparation  of,  455 

percentage  of  moisture  in,  469 
et  seq. 

,,      scorching  of,  353,  361 
,,      sized,  testing  of,  459 
.,     soft  spun,  266 
,,      suitable  for,  heavy  sizing,  266 
,,      tendering  of,  223 
,,     unsized,  366 
Yellow  mildew,  513 


Z 

Zinc,  chloride  of,  235 

,,    adulteration  of,  238  et  seq. 
,,    analyses  of  different  samples, 
253 

,,  detection  of  adulterants  in,  239 
et  seq. 

,,    free  acid  in,  247 

,,    manufacture  of,  235 

,,  percentage  of  required  to  pre- 
serve cloth  from  mildew,  85, 
254,  518 

,,    specific  gravity  of,  240 

,,  Twaddell  of,  as  indication  of 
strength,  240,  284 


Advertisements, 


i. 


On  pages  i.  to  iii.  of  The  Appendix  of  Bean  and  McCleary's 
"  Chemistry  and  Practice  of  Finishing,"  and  as  suggested  in  pages 
106  and  121  of  this  book  the  authors  say 

'  '  There  is,  however,  a  very  wide  and  comparatively 
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Specialization  in  this  hitherto  unexplored  field  is  our  business. 
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ii. 


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